提交 31246570 编写于 作者: 每日一练社区's avatar 每日一练社区

优化45题选项生成

上级 8b4f11f6
...@@ -2,33 +2,58 @@ ...@@ -2,33 +2,58 @@
<p>给你 <code>n</code> 个非负整数 <code>a<sub>1</sub>,a<sub>2,</sub>...,a</code><sub><code>n</code>,</sub>每个数代表坐标中的一个点 <code>(i, a<sub>i</sub>)</code> 。在坐标内画 <code>n</code> 条垂直线,垂直线 <code>i</code> 的两个端点分别为 <code>(i, a<sub>i</sub>)</code> 和 <code>(i, 0)</code> 。找出其中的两条线,使得它们与 <code>x</code> 轴共同构成的容器可以容纳最多的水。</p><p><strong>说明:</strong>你不能倾斜容器。</p><p> </p><p><strong>示例 1:</strong></p><p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0011.Container%20With%20Most%20Water/images/question_11.jpg" style="height: 287px; width: 600px;" /></p><pre><strong>输入:</strong>[1,8,6,2,5,4,8,3,7]<strong><br />输出:</strong>49 <strong><br />解释:</strong>图中垂直线代表输入数组 [1,8,6,2,5,4,8,3,7]。在此情况下,容器能够容纳水(表示为蓝色部分)的最大值为 49。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>height = [1,1]<strong><br />输出:</strong>1</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>height = [4,3,2,1,4]<strong><br />输出:</strong>16</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>height = [1,2,1]<strong><br />输出:</strong>2</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>n = height.length</code></li> <li><code>2 <= n <= 3 * 10<sup>4</sup></code></li> <li><code>0 <= height[i] <= 3 * 10<sup>4</sup></code></li></ul> <p>给你 <code>n</code> 个非负整数 <code>a<sub>1</sub>,a<sub>2,</sub>...,a</code><sub><code>n</code>,</sub>每个数代表坐标中的一个点 <code>(i, a<sub>i</sub>)</code> 。在坐标内画 <code>n</code> 条垂直线,垂直线 <code>i</code> 的两个端点分别为 <code>(i, a<sub>i</sub>)</code> 和 <code>(i, 0)</code> 。找出其中的两条线,使得它们与 <code>x</code> 轴共同构成的容器可以容纳最多的水。</p><p><strong>说明:</strong>你不能倾斜容器。</p><p> </p><p><strong>示例 1:</strong></p><p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0011.Container%20With%20Most%20Water/images/question_11.jpg" style="height: 287px; width: 600px;" /></p><pre><strong>输入:</strong>[1,8,6,2,5,4,8,3,7]<strong><br />输出:</strong>49 <strong><br />解释:</strong>图中垂直线代表输入数组 [1,8,6,2,5,4,8,3,7]。在此情况下,容器能够容纳水(表示为蓝色部分)的最大值为 49。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>height = [1,1]<strong><br />输出:</strong>1</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>height = [4,3,2,1,4]<strong><br />输出:</strong>16</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>height = [1,2,1]<strong><br />输出:</strong>2</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>n = height.length</code></li> <li><code>2 <= n <= 3 * 10<sup>4</sup></code></li> <li><code>0 <= height[i] <= 3 * 10<sup>4</sup></code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
class Solution
{
public:
int maxArea(vector<int> &height)
{
int ret = 0;
int temp;
for (int i = 0, j = height.size() - 1; i < j;)
{
temp = min(height[i], height[j]) * (j - i);
______________________
}
return ret;
}
};
```
## template ## template
```cpp ```cpp
#define MAX(a, b) (((a) < (b)) ? (b) : (a)) class Solution
#define MIN(a, b) (((a) > (b)) ? (b) : (a))
int maxArea(int *height, int heightSize)
{ {
int max = 0; public:
int i = 0, j = heightSize - 1; int maxArea(vector<int> &height)
int a; {
while (i < j) int ret = 0;
{ int temp;
a = MIN(height[i], height[j]) * (j - i); for (int i = 0, j = height.size() - 1; i < j;)
max = MAX(max, a); {
if (height[i] > height[j]) temp = min(height[i], height[j]) * (j - i);
--j; ret = ret > temp ? ret : temp;
else if (height[i] > height[j])
++i; j--;
} else
return max; i++;
} }
return ret;
}
};
``` ```
## 答案 ## 答案
```cpp ```cpp
ret = ret > temp ? ret : temp;
if (height[i] > height[j])
j--;
else
i++;
``` ```
## 选项 ## 选项
...@@ -36,17 +61,29 @@ int maxArea(int *height, int heightSize) ...@@ -36,17 +61,29 @@ int maxArea(int *height, int heightSize)
### A ### A
```cpp ```cpp
ret = ret > temp ? ret : temp;
if (height[i] < height[j])
j--;
else
i++;
``` ```
### B ### B
```cpp ```cpp
ret = ret > temp ? temp : ret;
if (height[i] < height[j])
j--;
else
i++;
``` ```
### C ### C
```cpp ```cpp
ret = ret > temp ? temp : ret;
if (height[i] < height[j])
i++;
else
j--;
``` ```
\ No newline at end of file
...@@ -2,6 +2,92 @@ ...@@ -2,6 +2,92 @@
<p>给定一个只包含数字的字符串,用以表示一个 IP 地址,返回所有可能从 <code>s</code> 获得的 <strong>有效 IP 地址 </strong>。你可以按任何顺序返回答案。</p><p><strong>有效 IP 地址</strong> 正好由四个整数(每个整数位于 0 到 255 之间组成,且不能含有前导 <code>0</code>),整数之间用 <code>'.'</code> 分隔。</p><p>例如:"0.1.2.201" 和 "192.168.1.1" 是 <strong>有效</strong> IP 地址,但是 "0.011.255.245"、"192.168.1.312" 和 "192.168@1.1" 是 <strong>无效</strong> IP 地址。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>s = "25525511135"<strong><br />输出:</strong>["255.255.11.135","255.255.111.35"]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>s = "0000"<strong><br />输出:</strong>["0.0.0.0"]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>s = "1111"<strong><br />输出:</strong>["1.1.1.1"]</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>s = "010010"<strong><br />输出:</strong>["0.10.0.10","0.100.1.0"]</pre><p><strong>示例 5:</strong></p><pre><strong>输入:</strong>s = "101023"<strong><br />输出:</strong>["1.0.10.23","1.0.102.3","10.1.0.23","10.10.2.3","101.0.2.3"]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= s.length <= 3000</code></li> <li><code>s</code> 仅由数字组成</li></ul> <p>给定一个只包含数字的字符串,用以表示一个 IP 地址,返回所有可能从 <code>s</code> 获得的 <strong>有效 IP 地址 </strong>。你可以按任何顺序返回答案。</p><p><strong>有效 IP 地址</strong> 正好由四个整数(每个整数位于 0 到 255 之间组成,且不能含有前导 <code>0</code>),整数之间用 <code>'.'</code> 分隔。</p><p>例如:"0.1.2.201" 和 "192.168.1.1" 是 <strong>有效</strong> IP 地址,但是 "0.011.255.245"、"192.168.1.312" 和 "192.168@1.1" 是 <strong>无效</strong> IP 地址。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>s = "25525511135"<strong><br />输出:</strong>["255.255.11.135","255.255.111.35"]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>s = "0000"<strong><br />输出:</strong>["0.0.0.0"]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>s = "1111"<strong><br />输出:</strong>["1.1.1.1"]</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>s = "010010"<strong><br />输出:</strong>["0.10.0.10","0.100.1.0"]</pre><p><strong>示例 5:</strong></p><pre><strong>输入:</strong>s = "101023"<strong><br />输出:</strong>["1.0.10.23","1.0.102.3","10.1.0.23","10.10.2.3","101.0.2.3"]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= s.length <= 3000</code></li> <li><code>s</code> 仅由数字组成</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
static bool valid(char *ip, int len)
{
if (len > 1 && ip[0] == '0')
{
return false;
}
if (len == 3)
{
int n = (ip[0] - '0') * 100 + (ip[1] - '0') * 10 + (ip[2] - '0');
if (n > 255)
{
return false;
}
}
return true;
}
#define WIDTH 4
static void dfs(char *s, int start, char *stack, int num, char **results, int *count)
{
int i, j;
if (num == 4)
{
if (s[start] == '\0')
{
results[*count] = malloc(3 * 4 + 3 + 1);
char *p = results[*count];
for (j = 0; j < num; j++)
{
char *q = stack + j * WIDTH;
______________________
}
(*count)++;
}
}
else
{
char *p = stack + num * WIDTH;
char *q = p;
for (i = start; s[i] != '\0' && i < start + 3; i++)
{
*q++ = s[i];
*q = '\0';
if (!valid(p, q - p))
{
return;
}
dfs(s, i + 1, stack, num + 1, results, count);
if (num + 1 < 4)
{
memset(stack + (num + 1) * WIDTH, 0, WIDTH);
}
}
}
}
static char **restoreIpAddresses(char *s, int *returnSize)
{
int count = 0;
char **results = malloc(100 * sizeof(char *));
char addr[16] = {'\0'};
dfs(s, 0, addr, 0, results, &count);
*returnSize = count;
return results;
}
int main(int argc, char **argv)
{
if (argc != 2)
{
fprintf(stderr, "Usage: ./test num\n");
exit(-1);
}
int i, count = 0;
char **list = restoreIpAddresses(argv[1], &count);
for (i = 0; i < count; i++)
{
printf("%s\n", list[i]);
}
}
```
## template ## template
```cpp ```cpp
...@@ -97,7 +183,13 @@ int main(int argc, char **argv) ...@@ -97,7 +183,13 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
while ((*p++ = *q++) != '\0')
{
}
if (j != 3)
{
*(p - 1) = '.';
}
``` ```
## 选项 ## 选项
...@@ -105,17 +197,37 @@ int main(int argc, char **argv) ...@@ -105,17 +197,37 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
while ((*p++ = *q++) != '\0')
{
*p++;
}
if (j != 3)
{
*(p - 1) = '.';
}
``` ```
### B ### B
```cpp ```cpp
while ((*p++ = *q++) != '\0')
{
*p++;
}
if (j != 3)
{
*p = '.';
}
``` ```
### C ### C
```cpp ```cpp
while ((*p++ = *q++) != '\0')
{
}
if (j != 3)
{
*p = '.';
}
``` ```
\ No newline at end of file
...@@ -9,6 +9,40 @@ ...@@ -9,6 +9,40 @@
<p><strong>示例&nbsp;2:</strong></p> <p><strong>示例&nbsp;2:</strong></p>
<pre><strong>输入:</strong>&nbsp;0<strong><br />输出:</strong>&nbsp;[0]<strong><br />解释:</strong> 我们定义格雷编码序列必须以 0 开头。给定编码总位数为 <em>n</em> 的格雷编码序列,其长度为 2<sup>n</sup>。当 <em>n</em> = 0 时,长度为 2<sup>0</sup> = 1。因此,当 <em>n</em> = 0 时,其格雷编码序列为 [0]。</pre> <pre><strong>输入:</strong>&nbsp;0<strong><br />输出:</strong>&nbsp;[0]<strong><br />解释:</strong> 我们定义格雷编码序列必须以 0 开头。给定编码总位数为 <em>n</em> 的格雷编码序列,其长度为 2<sup>n</sup>。当 <em>n</em> = 0 时,长度为 2<sup>0</sup> = 1。因此,当 <em>n</em> = 0 时,其格雷编码序列为 [0]。</pre>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
int *grayCode(int n, int *returnSize)
{
if (n < 0)
{
return NULL;
}
int i, count = 1 << n;
int *codes = malloc(count * sizeof(int));
_________________
return codes;
}
int main(int argc, char **argv)
{
if (argc != 2)
{
fprintf(stderr, "Usage: ./test n\n");
exit(-1);
}
int i, count;
int *list = grayCode(atoi(argv[1]), &count);
for (i = 0; i < count; i++)
{
printf("%d ", list[i]);
}
printf("\n");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -50,7 +84,11 @@ int main(int argc, char **argv) ...@@ -50,7 +84,11 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
for (i = 0; i < count; i++)
{
codes[i] = (i >> 1) ^ i;
}
*returnSize = 1 << n;
``` ```
## 选项 ## 选项
...@@ -58,17 +96,29 @@ int main(int argc, char **argv) ...@@ -58,17 +96,29 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
for (i = 0; i < count; i++)
{
codes[i] = (i >> 1) ^ i;
}
*returnSize = 1 << n - 1;
``` ```
### B ### B
```cpp ```cpp
for (i = 0; i < count; i++)
{
codes[i] = (i >> 2) ^ i;
}
*returnSize = 1 << n;
``` ```
### C ### C
```cpp ```cpp
for (i = 0; i < count; i++)
{
codes[i] = (i >> 1) ^ i;
}
*returnSize = 1 >> n;
``` ```
\ No newline at end of file
...@@ -2,6 +2,36 @@ ...@@ -2,6 +2,36 @@
<p>实现获取 <strong>下一个排列</strong> 的函数,算法需要将给定数字序列重新排列成字典序中下一个更大的排列。</p><p>如果不存在下一个更大的排列,则将数字重新排列成最小的排列(即升序排列)。</p><p>必须<strong><a href="https://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95" target="_blank"> 原地 </a></strong>修改,只允许使用额外常数空间。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [1,2,3]<strong><br />输出:</strong>[1,3,2]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [3,2,1]<strong><br />输出:</strong>[1,2,3]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>nums = [1,1,5]<strong><br />输出:</strong>[1,5,1]</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>nums = [1]<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 100</code></li> <li><code>0 <= nums[i] <= 100</code></li></ul> <p>实现获取 <strong>下一个排列</strong> 的函数,算法需要将给定数字序列重新排列成字典序中下一个更大的排列。</p><p>如果不存在下一个更大的排列,则将数字重新排列成最小的排列(即升序排列)。</p><p>必须<strong><a href="https://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95" target="_blank"> 原地 </a></strong>修改,只允许使用额外常数空间。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [1,2,3]<strong><br />输出:</strong>[1,3,2]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [3,2,1]<strong><br />输出:</strong>[1,2,3]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>nums = [1,1,5]<strong><br />输出:</strong>[1,5,1]</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>nums = [1]<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 100</code></li> <li><code>0 <= nums[i] <= 100</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
void nextPermutation(vector<int> &nums)
{
if (nums.size() < 2)
{
return;
}
int i = nums.size() - 2;
while (i >= 0 && nums[i] >= nums[i + 1])
{
i--;
}
if (i >= 0)
{
int j = nums.size() - 1;
________________________
swap(nums.begin() + i, nums.begin() + j);
}
reverse(nums.begin() + i + 1, nums.end());
}
};
```
## template ## template
```cpp ```cpp
...@@ -38,7 +68,10 @@ public: ...@@ -38,7 +68,10 @@ public:
## 答案 ## 答案
```cpp ```cpp
while (j >= 0 && nums[j] >= nums[i])
{
j--;
}
``` ```
## 选项 ## 选项
...@@ -46,17 +79,26 @@ public: ...@@ -46,17 +79,26 @@ public:
### A ### A
```cpp ```cpp
while (nums[j] >= nums[i])
{
j--;
}
``` ```
### B ### B
```cpp ```cpp
while (j >= 0)
{
j--;
}
``` ```
### C ### C
```cpp ```cpp
while (nums[j] < nums[i])
{
j--;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,41 @@ ...@@ -2,6 +2,41 @@
<p>给你一个整数数组 <code>nums</code> ,其中可能包含重复元素,请你返回该数组所有可能的子集(幂集)。</p><p>解集 <strong>不能</strong> 包含重复的子集。返回的解集中,子集可以按 <strong>任意顺序</strong> 排列。</p><div class="original__bRMd"><div><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [1,2,2]<strong><br />输出:</strong>[[],[1],[1,2],[1,2,2],[2],[2,2]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [0]<strong><br />输出:</strong>[[],[0]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 10</code></li> <li><code>-10 <= nums[i] <= 10</code></li></ul></div></div> <p>给你一个整数数组 <code>nums</code> ,其中可能包含重复元素,请你返回该数组所有可能的子集(幂集)。</p><p>解集 <strong>不能</strong> 包含重复的子集。返回的解集中,子集可以按 <strong>任意顺序</strong> 排列。</p><div class="original__bRMd"><div><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [1,2,2]<strong><br />输出:</strong>[[],[1],[1,2],[1,2,2],[2],[2,2]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [0]<strong><br />输出:</strong>[[],[0]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 10</code></li> <li><code>-10 <= nums[i] <= 10</code></li></ul></div></div>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<int>> subsetsWithDup(vector<int> &nums)
{
vector<vector<int>> res;
sort(nums.begin(), nums.end());
dfs(nums, 0, res);
return res;
}
private:
vector<int> stack;
void dfs(vector<int> &nums, int start, vector<vector<int>> &res)
{
res.push_back(stack);
int last = INT_MIN;
for (int i = start; i < nums.size(); i++)
{
if (last != nums[i])
{
stack.push_back(nums[i]);
____________________
stack.pop_back();
}
last = nums[i];
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -40,7 +75,7 @@ private: ...@@ -40,7 +75,7 @@ private:
## 答案 ## 答案
```cpp ```cpp
dfs(nums, i + 1, res);
``` ```
## 选项 ## 选项
...@@ -48,17 +83,17 @@ private: ...@@ -48,17 +83,17 @@ private:
### A ### A
```cpp ```cpp
dfs(nums, i - 1, res);
``` ```
### B ### B
```cpp ```cpp
dfs(nums, i, res);
``` ```
### C ### C
```cpp ```cpp
dfs(nums, 1, res);
``` ```
\ No newline at end of file
...@@ -2,6 +2,99 @@ ...@@ -2,6 +2,99 @@
<p>给你一个字符串 <code>path</code> ,表示指向某一文件或目录的 Unix 风格 <strong>绝对路径 </strong>(以 <code>'/'</code> 开头),请你将其转化为更加简洁的规范路径。</p><p class="MachineTrans-lang-zh-CN">在 Unix 风格的文件系统中,一个点(<code>.</code>)表示当前目录本身;此外,两个点 (<code>..</code>) 表示将目录切换到上一级(指向父目录);两者都可以是复杂相对路径的组成部分。任意多个连续的斜杠(即,<code>'//'</code>)都被视为单个斜杠 <code>'/'</code> 。 对于此问题,任何其他格式的点(例如,<code>'...'</code>)均被视为文件/目录名称。</p><p>请注意,返回的 <strong>规范路径</strong> 必须遵循下述格式:</p><ul> <li>始终以斜杠 <code>'/'</code> 开头。</li> <li>两个目录名之间必须只有一个斜杠 <code>'/'</code></li> <li>最后一个目录名(如果存在)<strong>不能 </strong><code>'/'</code> 结尾。</li> <li>此外,路径仅包含从根目录到目标文件或目录的路径上的目录(即,不含 <code>'.'</code><code>'..'</code>)。</li></ul><p>返回简化后得到的 <strong>规范路径</strong></p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>path = "/home/"<strong><br />输出:</strong>"/home"<strong><br />解释:</strong>注意,最后一个目录名后面没有斜杠。 </pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>path = "/../"<strong><br />输出:</strong>"/"<strong><br />解释:</strong>从根目录向上一级是不可行的,因为根目录是你可以到达的最高级。</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>path = "/home//foo/"<strong><br />输出:</strong>"/home/foo"<strong><br />解释:</strong>在规范路径中,多个连续斜杠需要用一个斜杠替换。</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>path = "/a/./b/../../c/"<strong><br />输出:</strong>"/c"</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= path.length <= 3000</code></li> <li><code>path</code> 由英文字母,数字,<code>'.'</code><code>'/'</code><code>'_'</code> 组成。</li> <li><code>path</code> 是一个有效的 Unix 风格绝对路径。</li></ul> <p>给你一个字符串 <code>path</code> ,表示指向某一文件或目录的 Unix 风格 <strong>绝对路径 </strong>(以 <code>'/'</code> 开头),请你将其转化为更加简洁的规范路径。</p><p class="MachineTrans-lang-zh-CN">在 Unix 风格的文件系统中,一个点(<code>.</code>)表示当前目录本身;此外,两个点 (<code>..</code>) 表示将目录切换到上一级(指向父目录);两者都可以是复杂相对路径的组成部分。任意多个连续的斜杠(即,<code>'//'</code>)都被视为单个斜杠 <code>'/'</code> 。 对于此问题,任何其他格式的点(例如,<code>'...'</code>)均被视为文件/目录名称。</p><p>请注意,返回的 <strong>规范路径</strong> 必须遵循下述格式:</p><ul> <li>始终以斜杠 <code>'/'</code> 开头。</li> <li>两个目录名之间必须只有一个斜杠 <code>'/'</code></li> <li>最后一个目录名(如果存在)<strong>不能 </strong><code>'/'</code> 结尾。</li> <li>此外,路径仅包含从根目录到目标文件或目录的路径上的目录(即,不含 <code>'.'</code><code>'..'</code>)。</li></ul><p>返回简化后得到的 <strong>规范路径</strong></p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>path = "/home/"<strong><br />输出:</strong>"/home"<strong><br />解释:</strong>注意,最后一个目录名后面没有斜杠。 </pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>path = "/../"<strong><br />输出:</strong>"/"<strong><br />解释:</strong>从根目录向上一级是不可行的,因为根目录是你可以到达的最高级。</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>path = "/home//foo/"<strong><br />输出:</strong>"/home/foo"<strong><br />解释:</strong>在规范路径中,多个连续斜杠需要用一个斜杠替换。</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>path = "/a/./b/../../c/"<strong><br />输出:</strong>"/c"</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= path.length <= 3000</code></li> <li><code>path</code> 由英文字母,数字,<code>'.'</code><code>'/'</code><code>'_'</code> 组成。</li> <li><code>path</code> 是一个有效的 Unix 风格绝对路径。</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static char *simplifyPath(char *path)
{
int len = strlen(path);
if (len == 0)
{
return path;
}
char *p = path;
int *indexes = malloc(len * sizeof(int));
int depth = 0;
int name_start = 1;
while (*p != '\0')
{
if (*p == '/')
{
if (p > path && *(p - 1) != '/' && *(p - 1) != '.')
{
name_start = 1;
}
}
else if (*p == '.')
{
if (*(p + 1) == '\0' || *(p + 1) == '/')
{
p += 1;
}
else if (*(p + 1) == '.' && (*(p + 2) == '\0' || *(p + 2) == '/'))
{
if (depth > 0)
{
depth--;
name_start = 1;
}
p += 2;
}
else
{
indexes[depth++] = p - path;
while (*p != '/' && *p != '\0')
{
p++;
}
}
if (*p == '\0')
{
break;
}
}
else
{
if (name_start && depth >= 0)
{
indexes[depth++] = p - path;
name_start = 0;
}
}
p++;
}
int i;
char *result = malloc(len + 1);
char *q = result;
if (depth <= 0)
{
*q++ = '/';
}
else
{
for (i = 0; i < depth; i++)
{
____________________
}
}
*q = '\0';
return result;
}
int main(int argc, char **argv)
{
if (argc != 2)
{
fprintf(stderr, "Usage: ./test path\n");
exit(-1);
}
printf("%s\n", simplifyPath(argv[1]));
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -103,7 +196,12 @@ int main(int argc, char **argv) ...@@ -103,7 +196,12 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
p = path + indexes[i];
*q++ = '/';
while (*p != '/')
{
*q++ = *p++;
}
``` ```
## 选项 ## 选项
...@@ -111,17 +209,32 @@ int main(int argc, char **argv) ...@@ -111,17 +209,32 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
p = path + indexes[i++];
*q++ = '/';
while (*p == '/')
{
*q++ = *p++;
}
``` ```
### B ### B
```cpp ```cpp
p = path + indexes[i++];
*q++ = '/';
while (*p != '/')
{
*q++ = *p++;
}
``` ```
### C ### C
```cpp ```cpp
p = path + indexes[i];
*q++ = '/';
while (*p == '/')
{
*q++ = *p++;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,50 @@ ...@@ -2,6 +2,50 @@
<p>给你两个 <strong>非空</strong> 的链表,表示两个非负的整数。它们每位数字都是按照 <strong>逆序</strong> 的方式存储的,并且每个节点只能存储 <strong>一位</strong> 数字。</p><p>请你将两个数相加,并以相同形式返回一个表示和的链表。</p><p>你可以假设除了数字 0 之外,这两个数都不会以 0 开头。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0002.Add%20Two%20Numbers/images/addtwonumber1.jpg" style="width: 483px; height: 342px;" /><pre><strong>输入:</strong>l1 = [2,4,3], l2 = [5,6,4]<strong><br />输出:</strong>[7,0,8]<strong><br />解释:</strong>342 + 465 = 807.</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>l1 = [0], l2 = [0]<strong><br />输出:</strong>[0]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>l1 = [9,9,9,9,9,9,9], l2 = [9,9,9,9]<strong><br />输出:</strong>[8,9,9,9,0,0,0,1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>每个链表中的节点数在范围 <code>[1, 100]</code> 内</li> <li><code>0 <= Node.val <= 9</code></li> <li>题目数据保证列表表示的数字不含前导零</li></ul> <p>给你两个 <strong>非空</strong> 的链表,表示两个非负的整数。它们每位数字都是按照 <strong>逆序</strong> 的方式存储的,并且每个节点只能存储 <strong>一位</strong> 数字。</p><p>请你将两个数相加,并以相同形式返回一个表示和的链表。</p><p>你可以假设除了数字 0 之外,这两个数都不会以 0 开头。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0002.Add%20Two%20Numbers/images/addtwonumber1.jpg" style="width: 483px; height: 342px;" /><pre><strong>输入:</strong>l1 = [2,4,3], l2 = [5,6,4]<strong><br />输出:</strong>[7,0,8]<strong><br />解释:</strong>342 + 465 = 807.</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>l1 = [0], l2 = [0]<strong><br />输出:</strong>[0]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>l1 = [9,9,9,9,9,9,9], l2 = [9,9,9,9]<strong><br />输出:</strong>[8,9,9,9,0,0,0,1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>每个链表中的节点数在范围 <code>[1, 100]</code> 内</li> <li><code>0 <= Node.val <= 9</code></li> <li>题目数据保证列表表示的数字不含前导零</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
struct ListNode
{
int val;
struct ListNode *next;
};
struct ListNode *addTwoNumbers(struct ListNode *l1, struct ListNode *l2)
{
struct ListNode *pp = NULL, *p = l1;
struct ListNode *qp = NULL, *q = l2;
int carry = 0;
while (p != NULL && q != NULL)
{
p->val += q->val + carry;
carry = 0;
if (p->val >= 10)
{
carry = 1;
p->val -= 10;
}
pp = p;
p = p->next;
qp = q;
q = q->next;
}
if (q)
{
pp->next = p = q;
qp->next = NULL;
}
____________________
if (carry)
{
struct ListNode *n = (struct ListNode *)malloc(sizeof(struct ListNode));
n->val = 1;
n->next = NULL;
pp->next = n;
}
return l1;
}
```
## template ## template
```cpp ```cpp
...@@ -60,7 +104,18 @@ struct ListNode *addTwoNumbers(struct ListNode *l1, struct ListNode *l2) ...@@ -60,7 +104,18 @@ struct ListNode *addTwoNumbers(struct ListNode *l1, struct ListNode *l2)
## 答案 ## 答案
```cpp ```cpp
while (carry && p)
{
p->val += carry;
carry = 0;
if (p->val >= 10)
{
carry = 1;
p->val -= 10;
}
pp = p;
p = p->next;
}
``` ```
## 选项 ## 选项
...@@ -68,17 +123,50 @@ struct ListNode *addTwoNumbers(struct ListNode *l1, struct ListNode *l2) ...@@ -68,17 +123,50 @@ struct ListNode *addTwoNumbers(struct ListNode *l1, struct ListNode *l2)
### A ### A
```cpp ```cpp
while (carry && p)
{
p->val += carry;
carry = 0;
if (p->val >= 10)
{
carry = 1;
p->val -= 10;
}
p = p->next;
pp = p;
}
``` ```
### B ### B
```cpp ```cpp
while (carry && p)
{
p->val += carry;
carry = 0;
if (p->val >= 10)
{
carry += 1;
p->val -= 10;
}
p = p->next;
pp = p;
}
``` ```
### C ### C
```cpp ```cpp
while (carry && p)
{
p->val += carry;
carry = 0;
if (p->val >= 10)
{
carry += 1;
p->val -= 10;
}
p = p->next;
pp = p;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,83 @@ ...@@ -2,6 +2,83 @@
<p>给你一个链表的头节点 <code>head</code> 和一个特定值<em> </em><code>x</code> ,请你对链表进行分隔,使得所有 <strong>小于</strong> <code>x</code> 的节点都出现在 <strong>大于或等于</strong> <code>x</code> 的节点之前。</p><p>你应当 <strong>保留</strong> 两个分区中每个节点的初始相对位置。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0086.Partition%20List/images/partition.jpg" style="width: 662px; height: 222px;" /><pre><strong>输入:</strong>head = [1,4,3,2,5,2], x = 3<strong><br />输出</strong>:[1,2,2,4,3,5]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = [2,1], x = 2<strong><br />输出</strong>:[1,2]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点的数目在范围 <code>[0, 200]</code> 内</li> <li><code>-100 <= Node.val <= 100</code></li> <li><code>-200 <= x <= 200</code></li></ul> <p>给你一个链表的头节点 <code>head</code> 和一个特定值<em> </em><code>x</code> ,请你对链表进行分隔,使得所有 <strong>小于</strong> <code>x</code> 的节点都出现在 <strong>大于或等于</strong> <code>x</code> 的节点之前。</p><p>你应当 <strong>保留</strong> 两个分区中每个节点的初始相对位置。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0086.Partition%20List/images/partition.jpg" style="width: 662px; height: 222px;" /><pre><strong>输入:</strong>head = [1,4,3,2,5,2], x = 3<strong><br />输出</strong>:[1,2,2,4,3,5]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = [2,1], x = 2<strong><br />输出</strong>:[1,2]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点的数目在范围 <code>[0, 200]</code> 内</li> <li><code>-100 <= Node.val <= 100</code></li> <li><code>-200 <= x <= 200</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
struct ListNode
{
int val;
struct ListNode *next;
};
struct ListNode *partition(struct ListNode *head, int x)
{
struct ListNode dummy;
struct ListNode *prev1 = &dummy, *pivot;
dummy.next = head;
for (pivot = head; pivot != NULL; pivot = pivot->next)
{
if (pivot->val >= x)
{
break;
}
prev1 = pivot;
}
struct ListNode *p = pivot->next;
struct ListNode *prev2 = pivot;
while (p != NULL)
{
if (p->val < x)
{
__________________
}
else
{
prev2 = p;
p = p->next;
}
}
return dummy.next;
}
int main(int argc, char **argv)
{
if (argc < 2)
{
fprintf(stderr, "Usage: ./test target n1 n2 n3...\n");
exit(-1);
}
int i, target = atoi(argv[1]);
struct ListNode *head = NULL;
struct ListNode *prev = NULL;
struct ListNode *p;
for (i = 0; i < argc - 2; i++)
{
p = malloc(sizeof(*p));
p->val = atoi(argv[i + 2]);
p->next = NULL;
if (head == NULL)
{
head = p;
prev = head;
}
else
{
prev->next = p;
prev = p;
}
}
p = partition(head, target);
while (p != NULL)
{
printf("%d ", p->val);
p = p->next;
}
printf("\n");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -86,7 +163,11 @@ int main(int argc, char **argv) ...@@ -86,7 +163,11 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
prev2->next = p->next;
p->next = prev1->next;
prev1->next = p;
prev1 = p;
p = prev2->next;
``` ```
## 选项 ## 选项
...@@ -94,17 +175,29 @@ int main(int argc, char **argv) ...@@ -94,17 +175,29 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
p->next = prev1->next;
prev1->next = p;
prev2->next = p->next;
prev1 = p;
p = prev2->next;
``` ```
### B ### B
```cpp ```cpp
p->next = prev1->next;
prev1->next = p;
prev2->next = p->next;
p = prev2->next;
prev1 = p;
``` ```
### C ### C
```cpp ```cpp
p->next = prev1->next;
prev2->next = p->next;
prev1->next = p;
p = prev2->next;
prev1 = p;
``` ```
\ No newline at end of file
...@@ -70,6 +70,46 @@ M 1000</pre> ...@@ -70,6 +70,46 @@ M 1000</pre>
</ul> </ul>
</div> </div>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
struct rmap
{
char *r;
int v;
} units[] = {
{"M", 1000},
{"CM", 900},
{"D", 500},
{"CD", 400},
{"C", 100},
{"XC", 90},
{"L", 50},
{"XL", 40},
{"X", 10},
{"IX", 9},
{"V", 5},
{"IV", 4},
{"I", 1}};
#include <string.h>
char result[64];
char *intToRoman(int num)
{
result[0] = 0;
int ri = 0;
int i = 0;
while (num)
{
______________
else
{
i++;
}
}
return result;
}
```
## template ## template
```cpp ```cpp
...@@ -117,7 +157,11 @@ char *intToRoman(int num) ...@@ -117,7 +157,11 @@ char *intToRoman(int num)
## 答案 ## 答案
```cpp ```cpp
if (num >= units[i].v)
{
strcat(result, units[i].r);
num -= units[i].v;
}
``` ```
## 选项 ## 选项
...@@ -125,17 +169,29 @@ char *intToRoman(int num) ...@@ -125,17 +169,29 @@ char *intToRoman(int num)
### A ### A
```cpp ```cpp
if (num >= units[i].v)
{
strcat(result, units[i].r);
num = units[i].v;
}
``` ```
### B ### B
```cpp ```cpp
if (num <= units[i].v)
{
strcat(result, units[i].r);
num -= units[i].v;
}
``` ```
### C ### C
```cpp ```cpp
if (num <= units[i].v)
{
strcat(result, units[i].r);
num = units[i].v;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,49 @@ ...@@ -2,6 +2,49 @@
<p>给定一个可包含重复数字的序列 <code>nums</code><strong>按任意顺序</strong> 返回所有不重复的全排列。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [1,1,2]<strong><br />输出:</strong>[[1,1,2], [1,2,1], [2,1,1]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [1,2,3]<strong><br />输出:</strong>[[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 8</code></li> <li><code>-10 <= nums[i] <= 10</code></li></ul> <p>给定一个可包含重复数字的序列 <code>nums</code><strong>按任意顺序</strong> 返回所有不重复的全排列。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [1,1,2]<strong><br />输出:</strong>[[1,1,2], [1,2,1], [2,1,1]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [1,2,3]<strong><br />输出:</strong>[[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 8</code></li> <li><code>-10 <= nums[i] <= 10</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<int>> permuteUnique(vector<int> &nums)
{
vector<vector<int>> res;
vector<bool> used(nums.size());
sort(nums.begin(), nums.end());
dfs(nums, used, res);
return res;
}
private:
vector<int> stack;
void dfs(vector<int> &nums, vector<bool> &used, vector<vector<int>> &res)
{
if (stack.size() == nums.size())
{
res.push_back(stack);
}
else
{
for (int i = 0; i < nums.size(); i++)
{
if (!used[i])
{
_____________________
stack.push_back(nums[i]);
used[i] = true;
dfs(nums, used, res);
stack.pop_back();
used[i] = false;
}
}
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -51,7 +94,10 @@ private: ...@@ -51,7 +94,10 @@ private:
## 答案 ## 答案
```cpp ```cpp
if (i > 0 && !used[i - 1] && nums[i - 1] == nums[i])
{
continue;
}
``` ```
## 选项 ## 选项
...@@ -59,17 +105,26 @@ private: ...@@ -59,17 +105,26 @@ private:
### A ### A
```cpp ```cpp
if (i > 0 && !used[i - 1] && nums[i - 1] == nums[i])
{
break;
}
``` ```
### B ### B
```cpp ```cpp
if (nums[i - 1] == nums[i])
{
continue;
}
``` ```
### C ### C
```cpp ```cpp
if (nums[i - 1] == nums[i])
{
break;
}
``` ```
\ No newline at end of file
...@@ -3,6 +3,23 @@ ...@@ -3,6 +3,23 @@
<p>给定一个字符串,请你找出其中不含有重复字符的 <strong>最长子串 </strong>的长度。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入: </strong>s = "abcabcbb"<strong><br />输出: </strong>3 <strong><br />解释:</strong> 因为无重复字符的最长子串是 "abc",所以其长度为 3。</pre><p><strong>示例 2:</strong></p><pre><strong>输入: </strong>s = "bbbbb"<strong><br />输出: </strong>1<strong><br />解释: </strong>因为无重复字符的最长子串是 "b",所以其长度为 1。</pre><p><strong>示例 3:</strong></p><pre><strong>输入: </strong>s = "pwwkew"<strong><br />输出: </strong>3<strong><br />解释: </strong>因为无重复字符的最长子串是 "wke",所以其长度为 3。  <p>给定一个字符串,请你找出其中不含有重复字符的 <strong>最长子串 </strong>的长度。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入: </strong>s = "abcabcbb"<strong><br />输出: </strong>3 <strong><br />解释:</strong> 因为无重复字符的最长子串是 "abc",所以其长度为 3。</pre><p><strong>示例 2:</strong></p><pre><strong>输入: </strong>s = "bbbbb"<strong><br />输出: </strong>1<strong><br />解释: </strong>因为无重复字符的最长子串是 "b",所以其长度为 1。</pre><p><strong>示例 3:</strong></p><pre><strong>输入: </strong>s = "pwwkew"<strong><br />输出: </strong>3<strong><br />解释: </strong>因为无重复字符的最长子串是 "wke",所以其长度为 3。 
请注意,你的答案必须是 <strong>子串 </strong>的长度,"pwke" 是一个<em>子序列,</em>不是子串。</pre><p><strong>示例 4:</strong></p><pre><strong>输入: </strong>s = ""<strong><br />输出: </strong>0</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= s.length <= 5 * 10<sup>4</sup></code></li> <li><code>s</code> 由英文字母、数字、符号和空格组成</li></ul> 请注意,你的答案必须是 <strong>子串 </strong>的长度,"pwke" 是一个<em>子序列,</em>不是子串。</pre><p><strong>示例 4:</strong></p><pre><strong>输入: </strong>s = ""<strong><br />输出: </strong>0</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= s.length <= 5 * 10<sup>4</sup></code></li> <li><code>s</code> 由英文字母、数字、符号和空格组成</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
int hset[128];
int lengthOfLongestSubstring(char *s)
{
int i = 0, j = 0;
int m = 0;
memset(hset, 0, sizeof hset);
for (; s[j]; j++)
{
___________________
}
return m;
}
```
## template ## template
```cpp ```cpp
...@@ -25,7 +42,9 @@ int lengthOfLongestSubstring(char *s) ...@@ -25,7 +42,9 @@ int lengthOfLongestSubstring(char *s)
## 答案 ## 答案
```cpp ```cpp
i = hset[s[j]] > i ? hset[s[j]] : i;
m = m > j - i + 1 ? m : j - i + 1;
hset[s[j]] = j + 1;
``` ```
## 选项 ## 选项
...@@ -33,17 +52,23 @@ int lengthOfLongestSubstring(char *s) ...@@ -33,17 +52,23 @@ int lengthOfLongestSubstring(char *s)
### A ### A
```cpp ```cpp
i = hset[s[j]] > i ? hset[s[j]] : i;
m = m > j - i + 1 ? m : j - i + 1;
hset[s[j]] = j - 1;
``` ```
### B ### B
```cpp ```cpp
i = hset[s[j]] > i ? hset[s[j]] : i;
m = m > j - i + 1 ? j - i + 1 : m;
hset[s[j]] = j - 1;
``` ```
### C ### C
```cpp ```cpp
i = hset[s[j]] > i ? hset[s[j]] : i;
m = m > j - i + 1 ? j - i + 1 : m;
hset[s[j]] = j + 1;
``` ```
\ No newline at end of file
...@@ -28,6 +28,42 @@ ...@@ -28,6 +28,42 @@
<li><code>s</code> 只包含数字,并且可能包含前导零。</li> <li><code>s</code> 只包含数字,并且可能包含前导零。</li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static int numDecodings(char *s)
{
int len = strlen(s);
if (len == 0)
{
return 0;
}
int a = 1;
int b = s[0] == '0' ? 0 : a;
int c = b;
for (int i = 2; i <= len; i++)
{
_________________
a = b;
b = c;
}
return c;
}
int main(int argc, char **argv)
{
if (argc != 2)
{
fprintf(stderr, "Usage: ./test number\n");
exit(-1);
}
printf("%d\n", numDecodings(argv[1]));
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -72,7 +108,12 @@ int main(int argc, char **argv) ...@@ -72,7 +108,12 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
c = s[i - 1] == '0' ? 0 : b;
int num = (s[i - 2] - '0') * 10 + (s[i - 1] - '0');
if (num >= 10 && num <= 26)
{
c += a;
}
``` ```
## 选项 ## 选项
...@@ -80,17 +121,32 @@ int main(int argc, char **argv) ...@@ -80,17 +121,32 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
c = s[i - 1] == '0' ? b : 0;
int num = (s[i - 2] - '0') * 10 + (s[i - 1] - '0');
if (num >= 10 && num <= 26)
{
c += a;
}
``` ```
### B ### B
```cpp ```cpp
c = s[i - 1] == '0' ? b : 0;
int num = (s[i - 2] - '0') + (s[i - 1] - '0');
if (num >= 10 && num <= 26)
{
c += a;
}
``` ```
### C ### C
```cpp ```cpp
c = s[i - 1] == '0' ? 0 : b;
int num = (s[i - 2] - '0') + (s[i - 1] - '0') * 10;
if (num >= 10 && num <= 26)
{
c += a;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,51 @@ ...@@ -2,6 +2,51 @@
<p>给定两个整数,被除数&nbsp;<code>dividend</code>&nbsp;和除数&nbsp;<code>divisor</code>。将两数相除,要求不使用乘法、除法和 mod 运算符。</p><p>返回被除数&nbsp;<code>dividend</code>&nbsp;除以除数&nbsp;<code>divisor</code>&nbsp;得到的商。</p><p>整数除法的结果应当截去(<code>truncate</code>)其小数部分,例如:<code>truncate(8.345) = 8</code> 以及 <code>truncate(-2.7335) = -2</code></p><p>&nbsp;</p><p><strong>示例&nbsp;1:</strong></p><pre><strong>输入:</strong> dividend = 10, divisor = 3<strong><br />输出:</strong> 3<strong><br />解释: </strong>10/3 = truncate(3.33333..) = truncate(3) = 3</pre><p><strong>示例&nbsp;2:</strong></p><pre><strong>输入:</strong> dividend = 7, divisor = -3<strong><br />输出:</strong> -2<strong><br />解释:</strong> 7/-3 = truncate(-2.33333..) = -2</pre><p>&nbsp;</p><p><strong>提示:</strong></p><ul> <li>被除数和除数均为 32 位有符号整数。</li> <li>除数不为&nbsp;0。</li> <li>假设我们的环境只能存储 32 位有符号整数,其数值范围是 [&minus;2<sup>31</sup>,&nbsp; 2<sup>31&nbsp;</sup>&minus; 1]。本题中,如果除法结果溢出,则返回 2<sup>31&nbsp;</sup>&minus; 1。</li></ul> <p>给定两个整数,被除数&nbsp;<code>dividend</code>&nbsp;和除数&nbsp;<code>divisor</code>。将两数相除,要求不使用乘法、除法和 mod 运算符。</p><p>返回被除数&nbsp;<code>dividend</code>&nbsp;除以除数&nbsp;<code>divisor</code>&nbsp;得到的商。</p><p>整数除法的结果应当截去(<code>truncate</code>)其小数部分,例如:<code>truncate(8.345) = 8</code> 以及 <code>truncate(-2.7335) = -2</code></p><p>&nbsp;</p><p><strong>示例&nbsp;1:</strong></p><pre><strong>输入:</strong> dividend = 10, divisor = 3<strong><br />输出:</strong> 3<strong><br />解释: </strong>10/3 = truncate(3.33333..) = truncate(3) = 3</pre><p><strong>示例&nbsp;2:</strong></p><pre><strong>输入:</strong> dividend = 7, divisor = -3<strong><br />输出:</strong> -2<strong><br />解释:</strong> 7/-3 = truncate(-2.33333..) = -2</pre><p>&nbsp;</p><p><strong>提示:</strong></p><ul> <li>被除数和除数均为 32 位有符号整数。</li> <li>除数不为&nbsp;0。</li> <li>假设我们的环境只能存储 32 位有符号整数,其数值范围是 [&minus;2<sup>31</sup>,&nbsp; 2<sup>31&nbsp;</sup>&minus; 1]。本题中,如果除法结果溢出,则返回 2<sup>31&nbsp;</sup>&minus; 1。</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
int divide(int dividend, int divisor)
{
int signal = 1;
unsigned int dvd = dividend;
if (dividend < 0)
{
signal *= -1;
dvd = ~dvd + 1;
}
unsigned int dvs = divisor;
if (divisor < 0)
{
signal *= -1;
dvs = ~dvs + 1;
}
int shift = 0;
while (dvd > dvs << shift)
{
shift++;
}
unsigned int res = 0;
while (dvd >= dvs)
{
________________
}
if (signal == 1 && res >= INT_MAX)
{
return INT_MAX;
}
else
{
return res * signal;
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -55,7 +100,12 @@ public: ...@@ -55,7 +100,12 @@ public:
## 答案 ## 答案
```cpp ```cpp
while (dvd < dvs << shift)
{
shift--;
}
res |= (unsigned int)1 << shift;
dvd -= dvs << shift;
``` ```
## 选项 ## 选项
...@@ -63,17 +113,32 @@ public: ...@@ -63,17 +113,32 @@ public:
### A ### A
```cpp ```cpp
while (dvd < dvs << shift)
{
shift--;
}
res &= (unsigned int)1 << shift;
dvd -= dvs << shift;
``` ```
### B ### B
```cpp ```cpp
while (dvd < dvs << shift)
{
shift--;
}
res &= (unsigned int)1 >> shift;
dvd -= dvs << shift;
``` ```
### C ### C
```cpp ```cpp
while (dvd < dvs << shift)
{
shift--;
}
res |= (unsigned int)1 >> shift;
dvd -= dvs << shift;
``` ```
\ No newline at end of file
...@@ -2,6 +2,45 @@ ...@@ -2,6 +2,45 @@
<p>给你一个 <code>m</code> 行 <code>n</code> 列的矩阵 <code>matrix</code> ,请按照 <strong>顺时针螺旋顺序</strong> ,返回矩阵中的所有元素。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0054.Spiral%20Matrix/images/spiral1.jpg" style="width: 242px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,2,3],[4,5,6],[7,8,9]]<strong><br />输出:</strong>[1,2,3,6,9,8,7,4,5]</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0054.Spiral%20Matrix/images/spiral.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,2,3,4],[5,6,7,8],[9,10,11,12]]<strong><br />输出:</strong>[1,2,3,4,8,12,11,10,9,5,6,7]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == matrix.length</code></li> <li><code>n == matrix[i].length</code></li> <li><code>1 <= m, n <= 10</code></li> <li><code>-100 <= matrix[i][j] <= 100</code></li></ul> <p>给你一个 <code>m</code> 行 <code>n</code> 列的矩阵 <code>matrix</code> ,请按照 <strong>顺时针螺旋顺序</strong> ,返回矩阵中的所有元素。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0054.Spiral%20Matrix/images/spiral1.jpg" style="width: 242px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,2,3],[4,5,6],[7,8,9]]<strong><br />输出:</strong>[1,2,3,6,9,8,7,4,5]</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0054.Spiral%20Matrix/images/spiral.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,2,3,4],[5,6,7,8],[9,10,11,12]]<strong><br />输出:</strong>[1,2,3,4,8,12,11,10,9,5,6,7]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == matrix.length</code></li> <li><code>n == matrix[i].length</code></li> <li><code>1 <= m, n <= 10</code></li> <li><code>-100 <= matrix[i][j] <= 100</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<int> spiralOrder(vector<vector<int>> &matrix)
{
vector<int> ans;
if (matrix.size() == 0)
return ans;
int cir = 0;
int row = matrix.size();
int col = matrix[0].size();
int max_cir = int(min(matrix.size(), matrix[0].size()) + 1) / 2;
for (; cir < max_cir; cir++)
{
for (int i = cir; i < col - cir; i++)
{
ans.push_back(matrix[cir][i]);
}
for (int i = cir + 1; i < row - cir; i++)
{
ans.push_back(matrix[i][col - 1 - cir]);
}
__________________
for (int i = row - 2 - cir; i > cir && (col - 1 - cir != cir); i--)
{
ans.push_back(matrix[i][cir]);
}
}
return ans;
}
};
```
## template ## template
```cpp ```cpp
...@@ -10,61 +49,47 @@ using namespace std; ...@@ -10,61 +49,47 @@ using namespace std;
class Solution class Solution
{ {
public: public:
vector<int> spiralOrder(vector<vector<int>> &matrix) vector<int> spiralOrder(vector<vector<int>> &matrix)
{ {
vector<int> res; vector<int> ans;
int hor_top = 0; if (matrix.size() == 0)
int hor_bottom = matrix.size() - 1; return ans;
int ver_left = 0; int cir = 0;
int ver_right = matrix[0].size() - 1; int row = matrix.size();
int direction = 0; int col = matrix[0].size();
while (hor_top <= hor_bottom && ver_left <= ver_right) int max_cir = int(min(matrix.size(), matrix[0].size()) + 1) / 2;
{ for (; cir < max_cir; cir++)
switch (direction) {
{ for (int i = cir; i < col - cir; i++)
case 0: {
for (int i = ver_left; i <= ver_right; i++) ans.push_back(matrix[cir][i]);
{ }
res.push_back(matrix[hor_top][i]);
} for (int i = cir + 1; i < row - cir; i++)
hor_top++; {
break; ans.push_back(matrix[i][col - 1 - cir]);
case 1: }
for (int i = hor_top; i <= hor_bottom; i++) for (int i = col - 2 - cir; i >= cir && (row - 1 - cir != cir); i--)
{ {
res.push_back(matrix[i][ver_right]); ans.push_back(matrix[row - cir - 1][i]);
} }
ver_right--; for (int i = row - 2 - cir; i > cir && (col - 1 - cir != cir); i--)
break; {
case 2: ans.push_back(matrix[i][cir]);
for (int i = ver_right; i >= ver_left; i--) }
{ }
res.push_back(matrix[hor_bottom][i]); return ans;
} }
hor_bottom--;
break;
case 3:
for (int i = hor_bottom; i >= hor_top; i--)
{
res.push_back(matrix[i][ver_left]);
}
ver_left++;
break;
default:
break;
}
direction++;
direction %= 4;
}
return res;
}
}; };
``` ```
## 答案 ## 答案
```cpp ```cpp
for (int i = col - 2 - cir; i >= cir && (row - 1 - cir != cir); i--)
{
ans.push_back(matrix[row - cir - 1][i]);
}
``` ```
## 选项 ## 选项
...@@ -72,17 +97,26 @@ public: ...@@ -72,17 +97,26 @@ public:
### A ### A
```cpp ```cpp
for (int i = col - 2 - cir; i >= cir && (row - 1 - cir != cir); i--)
{
ans.push_back(matrix[row - cir + 1][i]);
}
``` ```
### B ### B
```cpp ```cpp
for (int i = col - 2 - cir; i >= cir && (row - 1 - cir != cir); i--)
{
ans.push_back(matrix[row - cir][i]);
}
``` ```
### C ### C
```cpp ```cpp
for (int i = col - 2 - cir;row - 1 - cir != cir; i--)
{
ans.push_back(matrix[row - cir + 1][i]);
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,43 @@ ...@@ -2,6 +2,43 @@
<p>给定一个<strong> 没有重复</strong> 数字的序列,返回其所有可能的全排列。</p><p><strong>示例:</strong></p><pre><strong>输入:</strong> [1,2,3]<strong><br />输出:</strong>[ [1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], [3,2,1]]</pre> <p>给定一个<strong> 没有重复</strong> 数字的序列,返回其所有可能的全排列。</p><p><strong>示例:</strong></p><pre><strong>输入:</strong> [1,2,3]<strong><br />输出:</strong>[ [1,2,3], [1,3,2], [2,1,3], [2,3,1], [3,1,2], [3,2,1]]</pre>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<int>> permute(vector<int> &nums)
{
vector<vector<int>> res;
vector<bool> used(nums.size());
dfs(nums, used, res);
return res;
}
private:
vector<int> stack;
void dfs(vector<int> &nums, vector<bool> &used, vector<vector<int>> &res)
{
if (stack.size() == nums.size())
{
res.push_back(stack);
}
else
{
for (int i = 0; i < nums.size(); i++)
{
if (!used[i])
{
_______________
}
}
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -46,7 +83,11 @@ private: ...@@ -46,7 +83,11 @@ private:
## 答案 ## 答案
```cpp ```cpp
used[i] = true;
stack.push_back(nums[i]);
dfs(nums, used, res);
stack.pop_back();
used[i] = false;
``` ```
## 选项 ## 选项
...@@ -54,17 +95,26 @@ private: ...@@ -54,17 +95,26 @@ private:
### A ### A
```cpp ```cpp
used[i] = false;
stack.push_back(nums[i]);
dfs(nums, used, res);
stack.pop_back();
used[i] = true;
``` ```
### B ### B
```cpp ```cpp
stack.push_back(nums[i]);
dfs(nums, used, res);
stack.pop_back();
used[i] = true;
``` ```
### C ### C
```cpp ```cpp
stack.push_back(nums[i]);
dfs(nums, used, res);
stack.pop_back();
``` ```
\ No newline at end of file
...@@ -27,6 +27,46 @@ ...@@ -27,6 +27,46 @@
<p> </p> <p> </p>
<p><strong>进阶:</strong>你可以设计一个时间复杂度为 <code>O(log n)</code> 的解决方案吗?</p> <p><strong>进阶:</strong>你可以设计一个时间复杂度为 <code>O(log n)</code> 的解决方案吗?</p>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
int search(vector<int> &nums, int target)
{
int lo = 0;
int hi = nums.size() - 1;
for (lo <= hi)
{
int mid = lo + (hi - lo) / 2;
if (nums[mid] == target)
{
return mid;
}
if (nums[lo] <= nums[mid])
{
____________
}
else
{
if (nums[mid] < target && target <= nums[hi])
{
lo = mid + 1;
}
else
{
hi = mid - 1;
}
}
}
return -1;
}
};
```
## template ## template
```cpp ```cpp
...@@ -77,7 +117,14 @@ public: ...@@ -77,7 +117,14 @@ public:
## 答案 ## 答案
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
hi = mid - 1;
}
else
{
lo = mid + 1;
}
``` ```
## 选项 ## 选项
...@@ -85,17 +132,38 @@ public: ...@@ -85,17 +132,38 @@ public:
### A ### A
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
hi = mid + 1;
}
else
{
lo = mid - 1;
}
``` ```
### B ### B
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
lo = mid - 1;
}
else
{
hi = mid + 1;
}
``` ```
### C ### C
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
lo = mid + 1;
}
else
{
hi = mid - 1;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,99 @@ ...@@ -2,6 +2,99 @@
<p>编写一个高效的算法来判断 <code>m x n</code> 矩阵中,是否存在一个目标值。该矩阵具有如下特性:</p><ul> <li>每行中的整数从左到右按升序排列。</li> <li>每行的第一个整数大于前一行的最后一个整数。</li></ul><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0074.Search%20a%202D%20Matrix/images/mat.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 3<strong><br />输出:</strong>true</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0074.Search%20a%202D%20Matrix/images/mat2.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 13<strong><br />输出:</strong>false</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == matrix.length</code></li> <li><code>n == matrix[i].length</code></li> <li><code>1 <= m, n <= 100</code></li> <li><code>-10<sup>4</sup> <= matrix[i][j], target <= 10<sup>4</sup></code></li></ul> <p>编写一个高效的算法来判断 <code>m x n</code> 矩阵中,是否存在一个目标值。该矩阵具有如下特性:</p><ul> <li>每行中的整数从左到右按升序排列。</li> <li>每行的第一个整数大于前一行的最后一个整数。</li></ul><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0074.Search%20a%202D%20Matrix/images/mat.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 3<strong><br />输出:</strong>true</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0074.Search%20a%202D%20Matrix/images/mat2.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>matrix = [[1,3,5,7],[10,11,16,20],[23,30,34,60]], target = 13<strong><br />输出:</strong>false</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == matrix.length</code></li> <li><code>n == matrix[i].length</code></li> <li><code>1 <= m, n <= 100</code></li> <li><code>-10<sup>4</sup> <= matrix[i][j], target <= 10<sup>4</sup></code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
static int binary_search(int *nums, int len, int target)
{
int low = -1;
int high = len;
while (low + 1 < high)
{
int mid = low + (high - low) / 2;
if (target > nums[mid])
{
low = mid;
}
else
{
high = mid;
}
}
______________________
else
{
return high;
}
}
static bool searchMatrix(int **matrix, int matrixRowSize, int matrixColSize, int target)
{
if (matrixRowSize == 0 || matrixColSize == 0)
{
return false;
}
if (target < matrix[0][0] || target > matrix[matrixRowSize - 1][matrixColSize - 1])
{
return false;
}
int row = 0;
int *nums = NULL;
if (matrixRowSize > 0)
{
nums = malloc(matrixRowSize * sizeof(int));
for (row = 0; row < matrixRowSize; row++)
{
nums[row] = matrix[row][0];
}
row = binary_search(nums, matrixRowSize, target);
if (row >= 0)
{
return true;
}
else
{
row = -row - 1;
if (row == 0)
{
return false;
}
else
{
row--;
}
}
}
int col = binary_search(matrix[row], matrixColSize, target);
return col >= 0;
}
int main(int argc, char **argv)
{
int row = 3;
int col = 4;
int **mat = malloc(row * sizeof(int *));
mat[0] = malloc(col * sizeof(int));
mat[0][0] = 1;
mat[0][1] = 3;
mat[0][2] = 5;
mat[0][3] = 7;
mat[1] = malloc(col * sizeof(int));
mat[1][0] = 10;
mat[1][1] = 11;
mat[1][2] = 16;
mat[1][3] = 20;
mat[2] = malloc(col * sizeof(int));
mat[2][0] = 23;
mat[2][1] = 30;
mat[2][2] = 34;
mat[2][3] = 50;
printf("%s\n", searchMatrix(mat, row, col, atoi(argv[1])) ? "true" : "false");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -101,7 +194,10 @@ int main(int argc, char **argv) ...@@ -101,7 +194,10 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
if (high == len || nums[high] != target)
{
return -high - 1;
}
``` ```
## 选项 ## 选项
...@@ -109,17 +205,26 @@ int main(int argc, char **argv) ...@@ -109,17 +205,26 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
if (high == len || nums[high] != target)
{
return -high + 1;
}
``` ```
### B ### B
```cpp ```cpp
if (high == len || nums[high] != target)
{
return high - 1;
}
``` ```
### C ### C
```cpp ```cpp
if (high == len || nums[high] != target)
{
return high + 1;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,46 @@ ...@@ -2,6 +2,46 @@
<p>实现 <a href="https://www.cplusplus.com/reference/valarray/pow/" target="_blank">pow(<em>x</em>, <em>n</em>)</a> ,即计算 x 的 n 次幂函数(即,x<sup><span style="font-size:10.8333px">n</span></sup>)。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>x = 2.00000, n = 10<strong><br />输出:</strong>1024.00000</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>x = 2.10000, n = 3<strong><br />输出:</strong>9.26100</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>x = 2.00000, n = -2<strong><br />输出:</strong>0.25000<strong><br />解释:</strong>2<sup>-2</sup> = 1/2<sup>2</sup> = 1/4 = 0.25</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>-100.0 < x < 100.0</code></li> <li><code>-2<sup>31</sup> <= n <= 2<sup>31</sup>-1</code></li> <li><code>-10<sup>4</sup> <= x<sup>n</sup> <= 10<sup>4</sup></code></li></ul> <p>实现 <a href="https://www.cplusplus.com/reference/valarray/pow/" target="_blank">pow(<em>x</em>, <em>n</em>)</a> ,即计算 x 的 n 次幂函数(即,x<sup><span style="font-size:10.8333px">n</span></sup>)。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>x = 2.00000, n = 10<strong><br />输出:</strong>1024.00000</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>x = 2.10000, n = 3<strong><br />输出:</strong>9.26100</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>x = 2.00000, n = -2<strong><br />输出:</strong>0.25000<strong><br />解释:</strong>2<sup>-2</sup> = 1/2<sup>2</sup> = 1/4 = 0.25</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>-100.0 < x < 100.0</code></li> <li><code>-2<sup>31</sup> <= n <= 2<sup>31</sup>-1</code></li> <li><code>-10<sup>4</sup> <= x<sup>n</sup> <= 10<sup>4</sup></code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
double myPow(double x, int n)
{
if (n == INT_MIN)
{
double t = dfs(x, -(n / 2));
return 1 / t * 1 / t;
}
else
{
___________________
}
}
private:
double dfs(double x, int n)
{
if (n == 0)
{
return 1;
}
else if (n == 1)
{
return x;
}
else
{
double t = dfs(x, n / 2);
return (n % 2) ? (x * t * t) : (t * t);
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -45,7 +85,7 @@ private: ...@@ -45,7 +85,7 @@ private:
## 答案 ## 答案
```cpp ```cpp
return n < 0 ? 1 / dfs(x, -n) : dfs(x, n);
``` ```
## 选项 ## 选项
...@@ -53,17 +93,17 @@ private: ...@@ -53,17 +93,17 @@ private:
### A ### A
```cpp ```cpp
return n < 0 ? 1 / dfs(x, n) : dfs(x, -n);
``` ```
### B ### B
```cpp ```cpp
return n < 0 ? dfs(x, -n) : 1 / dfs(x, n);
``` ```
### C ### C
```cpp ```cpp
return n < 0 ? dfs(x, n) : 1 / dfs(x, -n);
``` ```
\ No newline at end of file
...@@ -9,6 +9,41 @@ ...@@ -9,6 +9,41 @@
<li>不考虑答案输出的顺序。</li> <li>不考虑答案输出的顺序。</li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<string>> groupAnagrams(vector<string> &strs)
{
vector<vector<string>> res;
unordered_map<string, vector<string>> ht;
for (const auto &str : strs)
{
int counts[26] = {0};
for (char c : str)
{
counts[c - 'a']++;
}
string key;
for (int i : counts)
{
________________
}
ht[key].push_back(str);
}
for (const auto &t : ht)
{
res.push_back(t.second);
}
return res;
}
};
```
## template ## template
```cpp ```cpp
...@@ -48,7 +83,8 @@ public: ...@@ -48,7 +83,8 @@ public:
## 答案 ## 答案
```cpp ```cpp
key.push_back('#');
key.push_back(i + '0');
``` ```
## 选项 ## 选项
...@@ -56,17 +92,20 @@ public: ...@@ -56,17 +92,20 @@ public:
### A ### A
```cpp ```cpp
key.push_back('#');
key.push_back('0');
``` ```
### B ### B
```cpp ```cpp
key.push_back(i + '#');
key.push_back(i + '0');
``` ```
### C ### C
```cpp ```cpp
key.push_back(i + '#');
key.push_back('0');
``` ```
\ No newline at end of file
...@@ -2,66 +2,82 @@ ...@@ -2,66 +2,82 @@
<p>给定一个 <code><em>m</em> x <em>n</em></code> 的矩阵,如果一个元素为 <strong>0 </strong>,则将其所在行和列的所有元素都设为 <strong>0</strong> 。请使用 <strong><a href="http://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95" target="_blank">原地</a></strong> 算法<strong>。</strong></p><p><strong>进阶:</strong></p><ul> <li>一个直观的解决方案是使用  <code>O(<em>m</em><em>n</em>)</code> 的额外空间,但这并不是一个好的解决方案。</li> <li>一个简单的改进方案是使用 <code>O(<em>m</em> + <em>n</em>)</code> 的额外空间,但这仍然不是最好的解决方案。</li> <li>你能想出一个仅使用常量空间的解决方案吗?</li></ul><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0073.Set%20Matrix%20Zeroes/images/mat1.jpg" style="width: 450px; height: 169px;" /><pre><strong>输入:</strong>matrix = [[1,1,1],[1,0,1],[1,1,1]]<strong><br />输出:</strong>[[1,0,1],[0,0,0],[1,0,1]]</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0073.Set%20Matrix%20Zeroes/images/mat2.jpg" style="width: 450px; height: 137px;" /><pre><strong>输入:</strong>matrix = [[0,1,2,0],[3,4,5,2],[1,3,1,5]]<strong><br />输出:</strong>[[0,0,0,0],[0,4,5,0],[0,3,1,0]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == matrix.length</code></li> <li><code>n == matrix[0].length</code></li> <li><code>1 <= m, n <= 200</code></li> <li><code>-2<sup>31</sup> <= matrix[i][j] <= 2<sup>31</sup> - 1</code></li></ul> <p>给定一个 <code><em>m</em> x <em>n</em></code> 的矩阵,如果一个元素为 <strong>0 </strong>,则将其所在行和列的所有元素都设为 <strong>0</strong> 。请使用 <strong><a href="http://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95" target="_blank">原地</a></strong> 算法<strong>。</strong></p><p><strong>进阶:</strong></p><ul> <li>一个直观的解决方案是使用  <code>O(<em>m</em><em>n</em>)</code> 的额外空间,但这并不是一个好的解决方案。</li> <li>一个简单的改进方案是使用 <code>O(<em>m</em> + <em>n</em>)</code> 的额外空间,但这仍然不是最好的解决方案。</li> <li>你能想出一个仅使用常量空间的解决方案吗?</li></ul><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0073.Set%20Matrix%20Zeroes/images/mat1.jpg" style="width: 450px; height: 169px;" /><pre><strong>输入:</strong>matrix = [[1,1,1],[1,0,1],[1,1,1]]<strong><br />输出:</strong>[[1,0,1],[0,0,0],[1,0,1]]</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0073.Set%20Matrix%20Zeroes/images/mat2.jpg" style="width: 450px; height: 137px;" /><pre><strong>输入:</strong>matrix = [[0,1,2,0],[3,4,5,2],[1,3,1,5]]<strong><br />输出:</strong>[[0,0,0,0],[0,4,5,0],[0,3,1,0]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == matrix.length</code></li> <li><code>n == matrix[0].length</code></li> <li><code>1 <= m, n <= 200</code></li> <li><code>-2<sup>31</sup> <= matrix[i][j] <= 2<sup>31</sup> - 1</code></li></ul>
## template 以下程序实现了这一功能,请你填补空白处内容:
```cpp ```cpp
#include <bits/stdc++.h> #include <bits/stdc++.h>
using namespace std; using namespace std;
class Solution
{
public: public:
void setZeroes(vector<vector<int>> &matrix) void setZeroes(vector<vector<int>> &matrix)
{
int i = matrix.size();
int j = matrix[0].size();
vector<int> hang(i);
vector<int> lie(j);
for (int m = 0; m < i; m++)
{
for (int n = 0; n < j; n++)
{
if (!matrix[m][n])
{
hang[m] = lie[n] = true;
}
}
}
for (int m = 0; m < i; m++)
{
for (int n = 0; n < j; n++)
{
__________________
}
}
}
};
```
## template
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{ {
bool bRow = false, bCol = false; public:
for (int row = 0; row < matrix.size(); row++) void setZeroes(vector<vector<int>> &matrix)
{ {
for (int col = 0; col < matrix[row].size(); col++) int i = matrix.size();
{ int j = matrix[0].size();
if (matrix[row][col] == 0) vector<int> hang(i);
{ vector<int> lie(j);
if (row == 0) for (int m = 0; m < i; m++)
{ {
bRow = true; for (int n = 0; n < j; n++)
} {
if (col == 0) if (!matrix[m][n])
{ {
bCol = true; hang[m] = lie[n] = true;
} }
matrix[0][col] = matrix[row][0] = 0; }
} }
} for (int m = 0; m < i; m++)
} {
for (int row = 1; row < matrix.size(); row++) for (int n = 0; n < j; n++)
{ {
for (int col = 1; col < matrix[row].size(); col++) if (hang[m] || lie[n])
{ matrix[m][n] = 0;
if (matrix[0][col] == 0 || matrix[row][0] == 0) }
{ }
matrix[row][col] = 0; }
} };
}
}
if (bRow)
{
for (auto &m : matrix[0])
{
m = 0;
}
}
if (bCol)
{
for (int row = 0; row < matrix.size(); row++)
{
matrix[row][0] = 0;
}
}
}
}
;
``` ```
## 答案 ## 答案
```cpp ```cpp
if (hang[m] || lie[n])
matrix[m][n] = 0;
``` ```
## 选项 ## 选项
...@@ -69,17 +85,20 @@ void setZeroes(vector<vector<int>> &matrix) ...@@ -69,17 +85,20 @@ void setZeroes(vector<vector<int>> &matrix)
### A ### A
```cpp ```cpp
if (hang[m] && lie[n])
matrix[m][n] = 0;
``` ```
### B ### B
```cpp ```cpp
if (hang[m] >= lie[n])
matrix[m][n] = 0;
``` ```
### C ### C
```cpp ```cpp
if (hang[m] <= lie[n])
matrix[m][n] = 0;
``` ```
\ No newline at end of file
...@@ -22,6 +22,68 @@ ...@@ -22,6 +22,68 @@
<li><code>-10<sup>9</sup> <= target <= 10<sup>9</sup></code></li> <li><code>-10<sup>9</sup> <= target <= 10<sup>9</sup></code></li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<int> searchRange(vector<int> &nums, int target)
{
vector<int> res;
res.push_back(binary_search_begin(nums, target));
res.push_back(binary_search_end(nums, target));
return res;
}
private:
int binary_search_begin(vector<int> nums, int target)
{
int lo = -1;
int hi = nums.size();
while (lo + 1 < hi)
{
int mid = lo + (hi - lo) / 2;
if (target > nums[mid])
{
lo = mid;
}
else
{
hi = mid;
}
}
if (hi == nums.size() || nums[hi] != target)
{
return -1;
}
else
{
return hi;
}
}
int binary_search_end(vector<int> nums, int target)
{
int lo = -1;
int hi = nums.size();
while (lo + 1 < hi)
{
int mid = lo + (hi - lo) / 2;
______________
}
if (lo == -1 || nums[lo] != target)
{
return -1;
}
else
{
return lo;
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -94,7 +156,14 @@ private: ...@@ -94,7 +156,14 @@ private:
## 答案 ## 答案
```cpp ```cpp
if (target < nums[mid])
{
hi = mid;
}
else
{
lo = mid;
}
``` ```
## 选项 ## 选项
...@@ -102,17 +171,38 @@ private: ...@@ -102,17 +171,38 @@ private:
### A ### A
```cpp ```cpp
if (target < nums[mid])
{
lo = mid;
}
else
{
hi = mid;
}
``` ```
### B ### B
```cpp ```cpp
if (target > nums[mid])
{
hi = mid;
}
else
{
lo = mid;
}
``` ```
### C ### C
```cpp ```cpp
if (target >= nums[mid])
{
hi = mid;
}
else
{
lo = mid;
}
``` ```
\ No newline at end of file
...@@ -8,6 +8,30 @@ ...@@ -8,6 +8,30 @@
<p><strong>说明:</strong></p> <p><strong>说明:</strong></p>
<p>假设你总是可以到达数组的最后一个位置。</p> <p>假设你总是可以到达数组的最后一个位置。</p>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
int jump(vector<int> &nums)
{
int steps = 0;
int lo = 0, hi = 0;
while (hi < nums.size() - 1)
{
int right = 0;
_______________________
hi = right;
steps++;
}
return steps;
}
};
```
## template ## template
```cpp ```cpp
...@@ -39,7 +63,11 @@ public: ...@@ -39,7 +63,11 @@ public:
## 答案 ## 答案
```cpp ```cpp
for (int i = lo; i <= hi; i++)
{
right = max(i + nums[i], right);
}
lo = hi + 1;
``` ```
## 选项 ## 选项
...@@ -47,17 +75,29 @@ public: ...@@ -47,17 +75,29 @@ public:
### A ### A
```cpp ```cpp
for (int i = lo; i <= hi; i++)
{
right = max(i + nums[i], right);
}
lo = hi - 1;
``` ```
### B ### B
```cpp ```cpp
for (int i = lo; i <= hi; i++)
{
right = max(nums[i], right);
}
lo = hi - 1;
``` ```
### C ### C
```cpp ```cpp
for (int i = lo; i <= hi; i++)
{
right = max(nums[i], right);
}
lo = hi + 1;
``` ```
\ No newline at end of file
...@@ -2,6 +2,65 @@ ...@@ -2,6 +2,65 @@
给你单链表的头指针 <code>head</code> 和两个整数 <code>left</code> 和 <code>right</code> ,其中 <code>left <= right</code> 。请你反转从位置 <code>left</code> 到位置 <code>right</code> 的链表节点,返回 <strong>反转后的链表</strong> 。<p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0092.Reverse%20Linked%20List%20II/images/rev2ex2.jpg" style="width: 542px; height: 222px;" /><pre><strong>输入:</strong>head = [1,2,3,4,5], left = 2, right = 4<strong><br />输出:</strong>[1,4,3,2,5]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = [5], left = 1, right = 1<strong><br />输出:</strong>[5]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点数目为 <code>n</code></li> <li><code>1 <= n <= 500</code></li> <li><code>-500 <= Node.val <= 500</code></li> <li><code>1 <= left <= right <= n</code></li></ul><p> </p><p><strong>进阶:</strong> 你可以使用一趟扫描完成反转吗?</p> 给你单链表的头指针 <code>head</code> 和两个整数 <code>left</code> 和 <code>right</code> ,其中 <code>left <= right</code> 。请你反转从位置 <code>left</code> 到位置 <code>right</code> 的链表节点,返回 <strong>反转后的链表</strong> 。<p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0092.Reverse%20Linked%20List%20II/images/rev2ex2.jpg" style="width: 542px; height: 222px;" /><pre><strong>输入:</strong>head = [1,2,3,4,5], left = 2, right = 4<strong><br />输出:</strong>[1,4,3,2,5]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = [5], left = 1, right = 1<strong><br />输出:</strong>[5]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点数目为 <code>n</code></li> <li><code>1 <= n <= 500</code></li> <li><code>-500 <= Node.val <= 500</code></li> <li><code>1 <= left <= right <= n</code></li></ul><p> </p><p><strong>进阶:</strong> 你可以使用一趟扫描完成反转吗?</p>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
struct ListNode
{
int val;
struct ListNode *next;
};
static struct ListNode *reverseBetween(struct ListNode *head, int m, int n)
{
int i;
struct ListNode dummy;
struct ListNode *prev = &dummy;
prev->next = head;
for (i = 1; i < m; i++)
{
prev = prev->next;
}
struct ListNode *p = prev->next;
for (i = m; i < n; i++)
{
struct ListNode *q = p->next;
__________________
}
return dummy.next;
}
int main(int argc, char **argv)
{
if (argc < 3)
{
fprintf(stderr, "Usage: ./test m n 1 2 3...\n");
exit(-1);
}
int i, count = argc - 3;
struct ListNode dummy;
struct ListNode *prev = &dummy;
struct ListNode *p;
for (i = 0; i < count; i++)
{
p = malloc(sizeof(*p));
p->val = atoi(argv[i + 3]);
p->next = NULL;
prev->next = p;
prev = p;
}
int m = atoi(argv[1]);
int n = atoi(argv[2]);
struct ListNode *head = reverseBetween(dummy.next, m, n);
for (p = head; p != NULL; p = p->next)
{
printf("%d ", p->val);
}
printf("\n");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -66,7 +125,9 @@ int main(int argc, char **argv) ...@@ -66,7 +125,9 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
p->next = q->next;
q->next = prev->next;
prev->next = q;
``` ```
## 选项 ## 选项
...@@ -74,17 +135,23 @@ int main(int argc, char **argv) ...@@ -74,17 +135,23 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
q->next = prev->next;
p->next = q->next;
prev->next = q;
``` ```
### B ### B
```cpp ```cpp
prev->next = q;
p->next = q->next;
q->next = prev->next;
``` ```
### C ### C
```cpp ```cpp
q->next = prev->next;
p->next = q->next;
prev->next = q;
``` ```
\ No newline at end of file
...@@ -2,6 +2,67 @@ ...@@ -2,6 +2,67 @@
<p>给定一个包含非负整数的 <code><em>m</em> x <em>n</em></code> 网格 <code>grid</code> ,请找出一条从左上角到右下角的路径,使得路径上的数字总和为最小。</p><p><strong>说明:</strong>每次只能向下或者向右移动一步。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0064.Minimum%20Path%20Sum/images/minpath.jpg" style="width: 242px; height: 242px;" /><pre><strong>输入:</strong>grid = [[1,3,1],[1,5,1],[4,2,1]]<strong><br />输出:</strong>7<strong><br />解释:</strong>因为路径 1→3→1→1→1 的总和最小。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>grid = [[1,2,3],[4,5,6]]<strong><br />输出:</strong>12</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>1 <= m, n <= 200</code></li> <li><code>0 <= grid[i][j] <= 100</code></li></ul> <p>给定一个包含非负整数的 <code><em>m</em> x <em>n</em></code> 网格 <code>grid</code> ,请找出一条从左上角到右下角的路径,使得路径上的数字总和为最小。</p><p><strong>说明:</strong>每次只能向下或者向右移动一步。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0064.Minimum%20Path%20Sum/images/minpath.jpg" style="width: 242px; height: 242px;" /><pre><strong>输入:</strong>grid = [[1,3,1],[1,5,1],[4,2,1]]<strong><br />输出:</strong>7<strong><br />解释:</strong>因为路径 1→3→1→1→1 的总和最小。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>grid = [[1,2,3],[4,5,6]]<strong><br />输出:</strong>12</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>1 <= m, n <= 200</code></li> <li><code>0 <= grid[i][j] <= 100</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static inline int min(int a, int b)
{
return a < b ? a : b;
}
int minPathSum(int **grid, int gridRowSize, int gridColSize)
{
int i, j;
int **dp = malloc(gridRowSize * sizeof(int *));
for (i = 0; i < gridRowSize; i++)
{
dp[i] = malloc(gridColSize * sizeof(int));
}
dp[0][0] = grid[0][0];
int sum = dp[0][0];
for (i = 1; i < gridRowSize; i++)
{
sum += grid[i][0];
dp[i][0] = sum;
}
sum = dp[0][0];
for (i = 1; i < gridColSize; i++)
{
sum += grid[0][i];
dp[0][i] = sum;
}
for (i = 1; i < gridRowSize; i++)
{
for (j = 1; j < gridColSize; j++)
{
_____________________
}
}
return dp[gridRowSize - 1][gridColSize - 1];
}
int main(int argc, char **argv)
{
int i, j;
int row = argc - 1;
int col = strlen(argv[1]);
int **grid = malloc(row * sizeof(int *));
for (i = 0; i < row; i++)
{
grid[i] = malloc(col * sizeof(int));
for (j = 0; j < col; j++)
{
grid[i][j] = argv[i + 1][j] - '0';
printf("%d ", grid[i][j]);
}
printf("\n");
}
printf("%d\n", minPathSum(grid, row, col));
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -66,7 +127,7 @@ int main(int argc, char **argv) ...@@ -66,7 +127,7 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
dp[i][j] = grid[i][j] + min(dp[i - 1][j], dp[i][j - 1]);
``` ```
## 选项 ## 选项
...@@ -74,17 +135,17 @@ int main(int argc, char **argv) ...@@ -74,17 +135,17 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
dp[i][j] = grid[i][j] + min(dp[i][j], dp[i - 1][j - 1]);
``` ```
### B ### B
```cpp ```cpp
dp[i][j] = grid[i][j] + min(dp[i][j - 1], dp[i - 1][j - 1]);
``` ```
### C ### C
```cpp ```cpp
dp[i][j] = grid[i][j] + min(dp[i - 1][j + 1], dp[i + 1][j - 1]);
``` ```
\ No newline at end of file
...@@ -2,6 +2,38 @@ ...@@ -2,6 +2,38 @@
<p>给你一个链表,删除链表的倒数第 <code>n</code><em> </em>个结点,并且返回链表的头结点。</p><p><strong>进阶:</strong>你能尝试使用一趟扫描实现吗?</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0019.Remove%20Nth%20Node%20From%20End%20of%20List/images/remove_ex1.jpg" style="width: 542px; height: 222px;" /><pre><strong>输入:</strong>head = [1,2,3,4,5], n = 2<strong><br />输出:</strong>[1,2,3,5]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = [1], n = 1<strong><br />输出:</strong>[]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>head = [1,2], n = 1<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中结点的数目为 <code>sz</code></li> <li><code>1 <= sz <= 30</code></li> <li><code>0 <= Node.val <= 100</code></li> <li><code>1 <= n <= sz</code></li></ul> <p>给你一个链表,删除链表的倒数第 <code>n</code><em> </em>个结点,并且返回链表的头结点。</p><p><strong>进阶:</strong>你能尝试使用一趟扫描实现吗?</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0019.Remove%20Nth%20Node%20From%20End%20of%20List/images/remove_ex1.jpg" style="width: 542px; height: 222px;" /><pre><strong>输入:</strong>head = [1,2,3,4,5], n = 2<strong><br />输出:</strong>[1,2,3,5]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = [1], n = 1<strong><br />输出:</strong>[]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>head = [1,2], n = 1<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中结点的数目为 <code>sz</code></li> <li><code>1 <= sz <= 30</code></li> <li><code>0 <= Node.val <= 100</code></li> <li><code>1 <= n <= sz</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
struct ListNode
{
int val;
ListNode *next;
ListNode() : val(0), next(nullptr) {}
ListNode(int x) : val(x), next(nullptr) {}
ListNode(int x, ListNode *next) : val(x), next(next) {}
};
#include <vector>
class Solution
{
public:
ListNode *removeNthFromEnd(ListNode *head, int n)
{
ListNode empty_node(0, head);
ListNode *p = &empty_node;
std::vector<ListNode *> pv;
while (p != nullptr)
{
pv.push_back(p);
p = p->next;
}
_________________
p->next = p->next->next;
return empty_node.next;
}
};
```
## template ## template
```cpp ```cpp
...@@ -37,7 +69,7 @@ public: ...@@ -37,7 +69,7 @@ public:
## 答案 ## 答案
```cpp ```cpp
p = pv[pv.size() - 1 - n];
``` ```
## 选项 ## 选项
...@@ -45,17 +77,17 @@ public: ...@@ -45,17 +77,17 @@ public:
### A ### A
```cpp ```cpp
p = pv[pv.size() + 1 - n];
``` ```
### B ### B
```cpp ```cpp
p = pv[pv.size() - 1 + n];
``` ```
### C ### C
```cpp ```cpp
p = pv[pv.size() + 1 + n];
``` ```
\ No newline at end of file
...@@ -21,6 +21,45 @@ ...@@ -21,6 +21,45 @@
<li><code>1 &lt;= target &lt;= 500</code></li> <li><code>1 &lt;= target &lt;= 500</code></li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<int>> combinationSum(vector<int> &candidates, int target)
{
vector<vector<int>> res;
dfs(candidates, 0, target, res);
return res;
}
private:
vector<int> stack;
void dfs(vector<int> &candidates, int start, int target, vector<vector<int>> &res)
{
if (target < 0)
{
return;
}
else if (target == 0)
{
res.push_back(stack);
}
else
{
for (int i = start; i < candidates.size(); i++)
{
stack.push_back(candidates[i]);
_____________________________
stack.pop_back();
}
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -63,7 +102,7 @@ private: ...@@ -63,7 +102,7 @@ private:
## 答案 ## 答案
```cpp ```cpp
dfs(candidates, i, target - candidates[i], res);
``` ```
## 选项 ## 选项
...@@ -71,17 +110,17 @@ private: ...@@ -71,17 +110,17 @@ private:
### A ### A
```cpp ```cpp
dfs(candidates, i, target - i, res);
``` ```
### B ### B
```cpp ```cpp
dfs(candidates, i, candidates[i], res);
``` ```
### C ### C
```cpp ```cpp
dfs(candidates, i, target + candidates[i], res);
``` ```
\ No newline at end of file
...@@ -2,6 +2,51 @@ ...@@ -2,6 +2,51 @@
<p>给你一个字符串 <code>s</code>,找到 <code>s</code> 中最长的回文子串。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>s = "babad"<strong><br />输出:</strong>"bab"<strong><br />解释:</strong>"aba" 同样是符合题意的答案。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>s = "cbbd"<strong><br />输出:</strong>"bb"</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>s = "a"<strong><br />输出:</strong>"a"</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>s = "ac"<strong><br />输出:</strong>"a"</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= s.length <= 1000</code></li> <li><code>s</code> 仅由数字和英文字母(大写和/或小写)组成</li></ul> <p>给你一个字符串 <code>s</code>,找到 <code>s</code> 中最长的回文子串。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>s = "babad"<strong><br />输出:</strong>"bab"<strong><br />解释:</strong>"aba" 同样是符合题意的答案。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>s = "cbbd"<strong><br />输出:</strong>"bb"</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>s = "a"<strong><br />输出:</strong>"a"</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>s = "ac"<strong><br />输出:</strong>"a"</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= s.length <= 1000</code></li> <li><code>s</code> 仅由数字和英文字母(大写和/或小写)组成</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
class Solution
{
public:
string longestPalindrome(string s)
{
int ti = 0, maxlen = 0, i, t;
for (i = 0; s[i]; i++)
{
t = 1;
while (t <= i && s[i + t])
{
if (s[i + t] == s[i - t])
t++;
else
break;
}
t--;
if (2 * t + 1 > maxlen)
{
ti = i - t;
maxlen = 2 * t + 1;
}
}
for (i = 0; s[i]; i++)
{
t = 1;
while (t <= i + 1 && s[i + t])
{
if (s[i - t + 1] == s[i + t])
t++;
else
break;
}
t--;
________________
}
s[ti + maxlen] = 0;
return s.c_str() + ti;
}
};
```
## template ## template
```cpp ```cpp
...@@ -54,7 +99,11 @@ public: ...@@ -54,7 +99,11 @@ public:
## 答案 ## 答案
```cpp ```cpp
if (2 * t > maxlen)
{
ti = i - t + 1;
maxlen = 2 * t;
}
``` ```
## 选项 ## 选项
...@@ -62,17 +111,29 @@ public: ...@@ -62,17 +111,29 @@ public:
### A ### A
```cpp ```cpp
if (t > maxlen)
{
ti = i - t + 1;
maxlen = 2 * t;
}
``` ```
### B ### B
```cpp ```cpp
if (2 * t > maxlen)
{
ti = i + t + 1;
maxlen = 2 * t;
}
``` ```
### C ### C
```cpp ```cpp
if (t > maxlen)
{
ti = i + t + 1;
maxlen = 2 * t;
}
``` ```
\ No newline at end of file
...@@ -31,6 +31,61 @@ ...@@ -31,6 +31,61 @@
<li>这会影响到程序的时间复杂度吗?会有怎样的影响,为什么?</li> <li>这会影响到程序的时间复杂度吗?会有怎样的影响,为什么?</li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
static bool search(int *nums, int numsSize, int target)
{
int lo = 0;
int hi = numsSize - 1;
while (lo <= hi)
{
int mid = lo + (hi - lo) / 2;
if (nums[mid] == target)
{
return true;
}
if (nums[lo] == nums[mid] && nums[mid] == nums[hi])
{
lo++;
hi--;
}
else if (nums[lo] <= nums[mid])
{
___________________
}
else
{
if (nums[mid] < target && target <= nums[hi])
{
lo = mid + 1;
}
else
{
hi = mid - 1;
}
}
}
return false;
}
int main(int argc, char **argv)
{
int i;
int target = atoi(argv[1]);
int size = argc - 2;
int *nums = malloc(size * sizeof(int));
for (i = 0; i < argc - 2; i++)
{
nums[i] = atoi(argv[i + 2]);
}
printf("%d\n", search(nums, size, target));
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -96,7 +151,14 @@ int main(int argc, char **argv) ...@@ -96,7 +151,14 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
hi = mid - 1;
}
else
{
lo = mid + 1;
}
``` ```
## 选项 ## 选项
...@@ -104,17 +166,38 @@ int main(int argc, char **argv) ...@@ -104,17 +166,38 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
hi = mid + 1;
}
else
{
lo = mid - 1;
}
``` ```
### B ### B
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
lo = mid + 1;
}
else
{
hi = mid - 1;
}
``` ```
### C ### C
```cpp ```cpp
if (nums[lo] <= target && target < nums[mid])
{
lo = mid - 1;
}
else
{
hi = mid + 1;
}
``` ```
\ No newline at end of file
...@@ -29,6 +29,51 @@ ...@@ -29,6 +29,51 @@
<li><code>nums</code> 已按升序排列</li> <li><code>nums</code> 已按升序排列</li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
static int removeDuplicates(int *nums, int numsSize)
{
if (numsSize == 0)
{
return 0;
}
int i;
int len = 0;
int count = 1;
for (i = 1; i < numsSize; i++)
{
if (nums[len] == nums[i])
{
_____________________
}
else
{
count = 1;
nums[++len] = nums[i];
}
}
return len + 1;
}
int main(int argc, char **argv)
{
int i, count = argc - 1;
int *nums = malloc(count * sizeof(int));
for (i = 0; i < count; i++)
{
nums[i] = atoi(argv[i + 1]);
}
count = removeDuplicates(nums, count);
for (i = 0; i < count; i++)
{
printf("%d ", nums[i]);
}
printf("\n");
}
```
## template ## template
```cpp ```cpp
...@@ -81,7 +126,11 @@ int main(int argc, char **argv) ...@@ -81,7 +126,11 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
if (count < 2)
{
count++;
nums[++len] = nums[i];
}
``` ```
## 选项 ## 选项
...@@ -89,17 +138,20 @@ int main(int argc, char **argv) ...@@ -89,17 +138,20 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
count++;
nums[++len] = nums[i];
``` ```
### B ### B
```cpp ```cpp
count++;
nums[len++] = nums[i];
``` ```
### C ### C
```cpp ```cpp
count++;
nums[--len] = nums[i];
``` ```
\ No newline at end of file
...@@ -2,6 +2,61 @@ ...@@ -2,6 +2,61 @@
<p>给定三个字符串 <code>s1</code>、<code>s2</code>、<code>s3</code>,请你帮忙验证 <code>s3</code> 是否是由 <code>s1</code> 和 <code>s2</code><em> </em><strong>交错 </strong>组成的。</p><p>两个字符串 <code>s</code> 和 <code>t</code> <strong>交错</strong> 的定义与过程如下,其中每个字符串都会被分割成若干 <strong>非空</strong> 子字符串:</p><ul> <li><code>s = s<sub>1</sub> + s<sub>2</sub> + ... + s<sub>n</sub></code></li> <li><code>t = t<sub>1</sub> + t<sub>2</sub> + ... + t<sub>m</sub></code></li> <li><code>|n - m| <= 1</code></li> <li><strong>交错</strong> 是 <code>s<sub>1</sub> + t<sub>1</sub> + s<sub>2</sub> + t<sub>2</sub> + s<sub>3</sub> + t<sub>3</sub> + ...</code> 或者 <code>t<sub>1</sub> + s<sub>1</sub> + t<sub>2</sub> + s<sub>2</sub> + t<sub>3</sub> + s<sub>3</sub> + ...</code></li></ul><p><strong>提示:</strong><code>a + b</code> 意味着字符串 <code>a</code> 和 <code>b</code> 连接。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0097.Interleaving%20String/images/interleave.jpg" style="width: 561px; height: 203px;" /><pre><strong>输入:</strong>s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"<strong><br />输出:</strong>true</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>s1 = "aabcc", s2 = "dbbca", s3 = "aadbbbaccc"<strong><br />输出:</strong>false</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>s1 = "", s2 = "", s3 = ""<strong><br />输出:</strong>true</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= s1.length, s2.length <= 100</code></li> <li><code>0 <= s3.length <= 200</code></li> <li><code>s1</code>、<code>s2</code>、和 <code>s3</code> 都由小写英文字母组成</li></ul> <p>给定三个字符串 <code>s1</code>、<code>s2</code>、<code>s3</code>,请你帮忙验证 <code>s3</code> 是否是由 <code>s1</code> 和 <code>s2</code><em> </em><strong>交错 </strong>组成的。</p><p>两个字符串 <code>s</code> 和 <code>t</code> <strong>交错</strong> 的定义与过程如下,其中每个字符串都会被分割成若干 <strong>非空</strong> 子字符串:</p><ul> <li><code>s = s<sub>1</sub> + s<sub>2</sub> + ... + s<sub>n</sub></code></li> <li><code>t = t<sub>1</sub> + t<sub>2</sub> + ... + t<sub>m</sub></code></li> <li><code>|n - m| <= 1</code></li> <li><strong>交错</strong> 是 <code>s<sub>1</sub> + t<sub>1</sub> + s<sub>2</sub> + t<sub>2</sub> + s<sub>3</sub> + t<sub>3</sub> + ...</code> 或者 <code>t<sub>1</sub> + s<sub>1</sub> + t<sub>2</sub> + s<sub>2</sub> + t<sub>3</sub> + s<sub>3</sub> + ...</code></li></ul><p><strong>提示:</strong><code>a + b</code> 意味着字符串 <code>a</code> 和 <code>b</code> 连接。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0097.Interleaving%20String/images/interleave.jpg" style="width: 561px; height: 203px;" /><pre><strong>输入:</strong>s1 = "aabcc", s2 = "dbbca", s3 = "aadbbcbcac"<strong><br />输出:</strong>true</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>s1 = "aabcc", s2 = "dbbca", s3 = "aadbbbaccc"<strong><br />输出:</strong>false</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>s1 = "", s2 = "", s3 = ""<strong><br />输出:</strong>true</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= s1.length, s2.length <= 100</code></li> <li><code>0 <= s3.length <= 200</code></li> <li><code>s1</code>、<code>s2</code>、和 <code>s3</code> 都由小写英文字母组成</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
static bool isInterleave(char *s1, char *s2, char *s3)
{
int i, j;
int len1 = strlen(s1);
int len2 = strlen(s2);
int len3 = strlen(s3);
if (len1 + len2 != len3)
{
return false;
}
bool *table = malloc((len1 + 1) * (len2 + 1) * sizeof(bool));
bool **dp = malloc((len1 + 1) * sizeof(bool *));
for (i = 0; i < len1 + 1; i++)
{
dp[i] = &table[i * (len2 + 1)];
}
dp[0][0] = true;
for (i = 1; i < len1 + 1; i++)
{
dp[i][0] = dp[i - 1][0] && s1[i - 1] == s3[i - 1];
}
for (i = 1; i < len2 + 1; i++)
{
____________________
}
for (i = 1; i < len1 + 1; i++)
{
for (j = 1; j < len2 + 1; j++)
{
bool up = dp[i - 1][j] && s1[i - 1] == s3[i + j - 1];
bool left = dp[i][j - 1] && s2[j - 1] == s3[i + j - 1];
dp[i][j] = up || left;
}
}
return dp[len1][len2];
}
int main(int argc, char **argv)
{
if (argc != 4)
{
fprintf(stderr, "Usage: ./test s1 s2 s3\n");
exit(-1);
}
printf("%s\n", isInterleave(argv[1], argv[2], argv[3]) ? "true" : "false");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -60,7 +115,7 @@ int main(int argc, char **argv) ...@@ -60,7 +115,7 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
dp[0][i] = dp[0][i - 1] && s2[i - 1] == s3[i - 1];
``` ```
## 选项 ## 选项
...@@ -68,17 +123,17 @@ int main(int argc, char **argv) ...@@ -68,17 +123,17 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
dp[0][i] = dp[0][i + 1] && s2[i - 1] == s3[i - 1];
``` ```
### B ### B
```cpp ```cpp
dp[0][i] = dp[0][i - 1] && s2[i + 1] == s3[i + 1];
``` ```
### C ### C
```cpp ```cpp
dp[0][i] = dp[0][i - 1];
``` ```
\ No newline at end of file
...@@ -2,6 +2,81 @@ ...@@ -2,6 +2,81 @@
<p>以数组 <code>intervals</code> 表示若干个区间的集合,其中单个区间为 <code>intervals[i] = [start<sub>i</sub>, end<sub>i</sub>]</code> 。请你合并所有重叠的区间,并返回一个不重叠的区间数组,该数组需恰好覆盖输入中的所有区间。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>intervals = [[1,3],[2,6],[8,10],[15,18]]<strong><br />输出:</strong>[[1,6],[8,10],[15,18]]<strong><br />解释:</strong>区间 [1,3] 和 [2,6] 重叠, 将它们合并为 [1,6].</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>intervals = [[1,4],[4,5]]<strong><br />输出:</strong>[[1,5]]<strong><br />解释:</strong>区间 [1,4] 和 [4,5] 可被视为重叠区间。</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= intervals.length <= 10<sup>4</sup></code></li> <li><code>intervals[i].length == 2</code></li> <li><code>0 <= start<sub>i</sub> <= end<sub>i</sub> <= 10<sup>4</sup></code></li></ul> <p>以数组 <code>intervals</code> 表示若干个区间的集合,其中单个区间为 <code>intervals[i] = [start<sub>i</sub>, end<sub>i</sub>]</code> 。请你合并所有重叠的区间,并返回一个不重叠的区间数组,该数组需恰好覆盖输入中的所有区间。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>intervals = [[1,3],[2,6],[8,10],[15,18]]<strong><br />输出:</strong>[[1,6],[8,10],[15,18]]<strong><br />解释:</strong>区间 [1,3] 和 [2,6] 重叠, 将它们合并为 [1,6].</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>intervals = [[1,4],[4,5]]<strong><br />输出:</strong>[[1,5]]<strong><br />解释:</strong>区间 [1,4] 和 [4,5] 可被视为重叠区间。</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= intervals.length <= 10<sup>4</sup></code></li> <li><code>intervals[i].length == 2</code></li> <li><code>0 <= start<sub>i</sub> <= end<sub>i</sub> <= 10<sup>4</sup></code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
static int compare(const void *a, const void *b)
{
return ((int *)a)[0] - ((int *)b)[0];
}
int **merge(int **intervals, int intervalsSize, int *intervalsColSize, int *returnSize, int **returnColumnSizes)
{
if (intervalsSize == 0)
{
*returnSize = 0;
return intervals;
}
int i, len = 0;
int *tmp = malloc(intervalsSize * 2 * sizeof(int));
for (i = 0; i < intervalsSize; i++)
{
tmp[i * 2] = intervals[i][0];
tmp[i * 2 + 1] = intervals[i][1];
}
qsort(tmp, intervalsSize, 2 * sizeof(int), compare);
intervals[0][0] = tmp[0];
intervals[0][1] = tmp[1];
for (i = 1; i < intervalsSize; i++)
{
if (tmp[i * 2] > intervals[len][1])
{
len++;
___________________________
}
else if (tmp[i * 2 + 1] > intervals[len][1])
{
intervals[len][1] = tmp[i * 2 + 1];
}
}
len += 1;
*returnSize = len;
*returnColumnSizes = malloc(len * sizeof(int));
for (i = 0; i < len; i++)
{
(*returnColumnSizes)[i] = 2;
}
return intervals;
}
int main(int argc, char **argv)
{
if (argc < 1 || argc % 2 == 0)
{
fprintf(stderr, "Usage: ./test s0 e0 s1 e1...");
exit(-1);
}
int i, count = 0;
int *sizes = malloc((argc - 1) / 2 * sizeof(int));
int **intervals = malloc((argc - 1) / 2 * sizeof(int *));
for (i = 0; i < (argc - 1) / 2; i++)
{
sizes[i] = 2;
intervals[i] = malloc(2 * sizeof(int));
intervals[i][0] = atoi(argv[i * 2 + 1]);
intervals[i][1] = atoi(argv[i * 2 + 2]);
}
int *col_sizes;
int **results = merge(intervals, (argc - 1) / 2, sizes, &count, &col_sizes);
for (i = 0; i < count; i++)
{
printf("[%d,%d]\n", results[i][0], results[i][1]);
}
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -81,7 +156,8 @@ int main(int argc, char **argv) ...@@ -81,7 +156,8 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
intervals[len][0] = tmp[i * 2];
intervals[len][1] = tmp[i * 2 + 1];
``` ```
## 选项 ## 选项
...@@ -89,17 +165,20 @@ int main(int argc, char **argv) ...@@ -89,17 +165,20 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
intervals[len][0] = tmp[i];
intervals[len][1] = tmp[i + 1];
``` ```
### B ### B
```cpp ```cpp
intervals[len][0] = tmp[i];
intervals[len][1] = tmp[i - 1];
``` ```
### C ### C
```cpp ```cpp
intervals[len][0] = tmp[i * 2];
intervals[len][1] = tmp[i * 2 - 1];
``` ```
\ No newline at end of file
...@@ -2,6 +2,62 @@ ...@@ -2,6 +2,62 @@
<p>给你一个包含 <code>n</code> 个整数的数组 <code>nums</code>,判断 <code>nums</code> 中是否存在三个元素 <em>a,b,c ,</em>使得 <em>a + b + c = </em>0 ?请你找出所有和为 <code>0</code> 且不重复的三元组。</p><p><strong>注意:</strong>答案中不可以包含重复的三元组。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [-1,0,1,2,-1,-4]<strong><br />输出:</strong>[[-1,-1,2],[-1,0,1]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = []<strong><br />输出:</strong>[]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>nums = [0]<strong><br />输出:</strong>[]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= nums.length <= 3000</code></li> <li><code>-10<sup>5</sup> <= nums[i] <= 10<sup>5</sup></code></li></ul> <p>给你一个包含 <code>n</code> 个整数的数组 <code>nums</code>,判断 <code>nums</code> 中是否存在三个元素 <em>a,b,c ,</em>使得 <em>a + b + c = </em>0 ?请你找出所有和为 <code>0</code> 且不重复的三元组。</p><p><strong>注意:</strong>答案中不可以包含重复的三元组。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [-1,0,1,2,-1,-4]<strong><br />输出:</strong>[[-1,-1,2],[-1,0,1]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = []<strong><br />输出:</strong>[]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>nums = [0]<strong><br />输出:</strong>[]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>0 <= nums.length <= 3000</code></li> <li><code>-10<sup>5</sup> <= nums[i] <= 10<sup>5</sup></code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <algorithm>
#include <set>
class Solution
{
public:
vector<vector<int>> threeSum(vector<int> &nums)
{
vector<vector<int>> r;
if (nums.size() == 0)
return r;
sort(nums.begin(), nums.end());
int cur, left, right;
cur = 0;
while (cur < nums.size())
{
if (nums[cur] > 0)
break;
left = cur + 1;
right = nums.size() - 1;
while (left < right)
{
int n = nums[cur] + nums[left] + nums[right];
if (n == 0)
{
r.emplace_back(vector<int>({nums[cur], nums[left], nums[right]}));
int t = left + 1;
__________________________
}
else if (n > 0)
{
int t = right - 1;
while (t > left && nums[t] == nums[right])
t--;
right = t;
}
else
{
int t = left + 1;
while (t < right && nums[t] == nums[left])
t++;
left = t;
}
}
int t = cur + 1;
while (t < nums.size() && nums[t] == nums[cur])
t++;
cur = t;
}
return r;
}
};
```
## template ## template
```cpp ```cpp
...@@ -67,7 +123,13 @@ public: ...@@ -67,7 +123,13 @@ public:
## 答案 ## 答案
```cpp ```cpp
while (t < right && nums[t] == nums[left])
t++;
left = t;
t = right - 1;
while (t > left && nums[t] == nums[right])
t--;
right = t;
``` ```
## 选项 ## 选项
...@@ -75,17 +137,35 @@ public: ...@@ -75,17 +137,35 @@ public:
### A ### A
```cpp ```cpp
while (t < right)
t++;
left = t;
t = right - 1;
while (t > left)
t--;
right = t;
``` ```
### B ### B
```cpp ```cpp
while (t < right)
t++;
left = t;
t = right + 1;
while (t > left)
t--;
right = t;
``` ```
### C ### C
```cpp ```cpp
while (t < right && nums[t] == nums[left])
t++;
left = t;
t = right + 1;
while (t > left && nums[t] == nums[right])
t--;
right = t;
``` ```
\ No newline at end of file
...@@ -2,6 +2,39 @@ ...@@ -2,6 +2,39 @@
<p>给定两个以字符串形式表示的非负整数&nbsp;<code>num1</code>&nbsp;&nbsp;<code>num2</code>,返回&nbsp;<code>num1</code>&nbsp;&nbsp;<code>num2</code>&nbsp;的乘积,它们的乘积也表示为字符串形式。</p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong> num1 = &quot;2&quot;, num2 = &quot;3&quot;<strong><br />输出:</strong> &quot;6&quot;</pre><p><strong>示例&nbsp;2:</strong></p><pre><strong>输入:</strong> num1 = &quot;123&quot;, num2 = &quot;456&quot;<strong><br />输出:</strong> &quot;56088&quot;</pre><p><strong>说明:</strong></p><ol> <li><code>num1</code>&nbsp;&nbsp;<code>num2</code>&nbsp;的长度小于110。</li> <li><code>num1</code>&nbsp;<code>num2</code> 只包含数字&nbsp;<code>0-9</code></li> <li><code>num1</code>&nbsp;<code>num2</code>&nbsp;均不以零开头,除非是数字 0 本身。</li> <li><strong>不能使用任何标准库的大数类型(比如 BigInteger)</strong><strong>直接将输入转换为整数来处理</strong></li></ol> <p>给定两个以字符串形式表示的非负整数&nbsp;<code>num1</code>&nbsp;&nbsp;<code>num2</code>,返回&nbsp;<code>num1</code>&nbsp;&nbsp;<code>num2</code>&nbsp;的乘积,它们的乘积也表示为字符串形式。</p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong> num1 = &quot;2&quot;, num2 = &quot;3&quot;<strong><br />输出:</strong> &quot;6&quot;</pre><p><strong>示例&nbsp;2:</strong></p><pre><strong>输入:</strong> num1 = &quot;123&quot;, num2 = &quot;456&quot;<strong><br />输出:</strong> &quot;56088&quot;</pre><p><strong>说明:</strong></p><ol> <li><code>num1</code>&nbsp;&nbsp;<code>num2</code>&nbsp;的长度小于110。</li> <li><code>num1</code>&nbsp;<code>num2</code> 只包含数字&nbsp;<code>0-9</code></li> <li><code>num1</code>&nbsp;<code>num2</code>&nbsp;均不以零开头,除非是数字 0 本身。</li> <li><strong>不能使用任何标准库的大数类型(比如 BigInteger)</strong><strong>直接将输入转换为整数来处理</strong></li></ol>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
string multiply(string num1, string num2)
{
string res(num1.length() + num2.length(), '0');
for (int i = num2.length() - 1; i >= 0; i--)
{
int j, carry = 0;
for (j = num1.length() - 1; j >= 0; j--)
{
_____________________
}
res[i + j + 1] = carry + '0';
}
int i;
for (i = 0; i < res.length() - 1; i++)
{
if (res[i] != '0')
{
break;
}
}
return res.substr(i);
}
};
```
## template ## template
```cpp ```cpp
...@@ -40,7 +73,9 @@ public: ...@@ -40,7 +73,9 @@ public:
## 答案 ## 答案
```cpp ```cpp
carry += (num1[j] - '0') * (num2[i] - '0') + (res[i + j + 1] - '0');
res[i + j + 1] = carry % 10 + '0';
carry /= 10;
``` ```
## 选项 ## 选项
...@@ -48,17 +83,23 @@ public: ...@@ -48,17 +83,23 @@ public:
### A ### A
```cpp ```cpp
carry += (num1[j] - '0') * (num2[i] - '0') + (res[i + j] - '0');
res[i + j] = carry % 10 + '0';
carry /= 10;
``` ```
### B ### B
```cpp ```cpp
carry += (num1[j] - '0') * (num2[i] - '0') + (res[i + j] - '0');
res[i + j] = carry % 10 + '0';
carry %= 10;
``` ```
### C ### C
```cpp ```cpp
carry += (num1[j] - '0') * (num2[i] - '0') + (res[i + j - 1] - '0');
res[i + j - 1] = carry % 10 + '0';
carry %= 10;
``` ```
\ No newline at end of file
...@@ -2,6 +2,54 @@ ...@@ -2,6 +2,54 @@
<p>给定一个包括&nbsp;<em>n</em> 个整数的数组&nbsp;<code>nums</code><em>&nbsp;</em>和 一个目标值&nbsp;<code>target</code>。找出&nbsp;<code>nums</code><em>&nbsp;</em>中的三个整数,使得它们的和与&nbsp;<code>target</code>&nbsp;最接近。返回这三个数的和。假定每组输入只存在唯一答案。</p><p>&nbsp;</p><p><strong>示例:</strong></p><pre><strong>输入:</strong>nums = [-1,2,1,-4], target = 1<strong><br />输出:</strong>2<strong><br />解释:</strong>与 target 最接近的和是 2 (-1 + 2 + 1 = 2) 。</pre><p>&nbsp;</p><p><strong>提示:</strong></p><ul> <li><code>3 &lt;= nums.length &lt;= 10^3</code></li> <li><code>-10^3&nbsp;&lt;= nums[i]&nbsp;&lt;= 10^3</code></li> <li><code>-10^4&nbsp;&lt;= target&nbsp;&lt;= 10^4</code></li></ul> <p>给定一个包括&nbsp;<em>n</em> 个整数的数组&nbsp;<code>nums</code><em>&nbsp;</em>和 一个目标值&nbsp;<code>target</code>。找出&nbsp;<code>nums</code><em>&nbsp;</em>中的三个整数,使得它们的和与&nbsp;<code>target</code>&nbsp;最接近。返回这三个数的和。假定每组输入只存在唯一答案。</p><p>&nbsp;</p><p><strong>示例:</strong></p><pre><strong>输入:</strong>nums = [-1,2,1,-4], target = 1<strong><br />输出:</strong>2<strong><br />解释:</strong>与 target 最接近的和是 2 (-1 + 2 + 1 = 2) 。</pre><p>&nbsp;</p><p><strong>提示:</strong></p><ul> <li><code>3 &lt;= nums.length &lt;= 10^3</code></li> <li><code>-10^3&nbsp;&lt;= nums[i]&nbsp;&lt;= 10^3</code></li> <li><code>-10^4&nbsp;&lt;= target&nbsp;&lt;= 10^4</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <cstdlib>
class Solution
{
public:
int threeSumClosest(vector<int> &nums, int target)
{
sort(nums.begin(), nums.end());
int cur, left, right;
cur = 0;
int closest = nums[0] + nums[1] + nums[2];
while (cur < nums.size() - 2)
{
left = cur + 1;
right = nums.size() - 1;
int n;
while (left < right)
{
n = nums[cur] + nums[left] + nums[right];
if (abs(target - n) < abs(target - closest))
{
closest = n;
}
if (n == target)
{
break;
}
____________________________
else
{
int t = left + 1;
while (t < right && nums[t] == nums[left])
t++;
left = t;
}
}
int t = cur + 1;
while (t < nums.size() && nums[t] == nums[cur])
t++;
cur = t;
}
return closest;
}
};
```
## template ## template
```cpp ```cpp
...@@ -59,7 +107,13 @@ public: ...@@ -59,7 +107,13 @@ public:
## 答案 ## 答案
```cpp ```cpp
else if (n > target)
{
int t = right - 1;
while (t > left && nums[t] == nums[right])
t--;
right = t;
}
``` ```
## 选项 ## 选项
...@@ -67,17 +121,35 @@ public: ...@@ -67,17 +121,35 @@ public:
### A ### A
```cpp ```cpp
else if (left > target)
{
int t = right + 1;
while (t > left && nums[t] == nums[right])
t--;
right = t;
}
``` ```
### B ### B
```cpp ```cpp
else if (left > target)
{
int t = right - 1;
while (t > left && nums[t] == nums[right])
t--;
right = t + 1;
}
``` ```
### C ### C
```cpp ```cpp
else if (left > target)
{
int t = right - 1;
while (t > left && nums[t] == nums[right])
t--;
right = t;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,39 @@ ...@@ -2,6 +2,39 @@
<p>给定一个非负整数数组 <code>nums</code> ,你最初位于数组的 <strong>第一个下标</strong></p><p>数组中的每个元素代表你在该位置可以跳跃的最大长度。</p><p>判断你是否能够到达最后一个下标。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [2,3,1,1,4]<strong><br />输出:</strong>true<strong><br />解释:</strong>可以先跳 1 步,从下标 0 到达下标 1, 然后再从下标 1 跳 3 步到达最后一个下标。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [3,2,1,0,4]<strong><br />输出:</strong>false<strong><br />解释:</strong>无论怎样,总会到达下标为 3 的位置。但该下标的最大跳跃长度是 0 , 所以永远不可能到达最后一个下标。</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 3 * 10<sup>4</sup></code></li> <li><code>0 <= nums[i] <= 10<sup>5</sup></code></li></ul> <p>给定一个非负整数数组 <code>nums</code> ,你最初位于数组的 <strong>第一个下标</strong></p><p>数组中的每个元素代表你在该位置可以跳跃的最大长度。</p><p>判断你是否能够到达最后一个下标。</p><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [2,3,1,1,4]<strong><br />输出:</strong>true<strong><br />解释:</strong>可以先跳 1 步,从下标 0 到达下标 1, 然后再从下标 1 跳 3 步到达最后一个下标。</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [3,2,1,0,4]<strong><br />输出:</strong>false<strong><br />解释:</strong>无论怎样,总会到达下标为 3 的位置。但该下标的最大跳跃长度是 0 , 所以永远不可能到达最后一个下标。</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= nums.length <= 3 * 10<sup>4</sup></code></li> <li><code>0 <= nums[i] <= 10<sup>5</sup></code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
static inline int max(int a, int b)
{
return a > b ? a : b;
}
static bool canJump(int *nums, int numsSize)
{
int i, pos = 0;
for (i = 0; i < numsSize - 1; i++)
{
___________________
pos = max(i + nums[i], pos);
}
return pos >= numsSize - 1;
}
int main(int argc, char **argv)
{
int i, count = argc - 1;
int *nums = malloc(count * sizeof(int));
for (i = 0; i < count; i++)
{
nums[i] = atoi(argv[i + 1]);
}
printf("%s\n", canJump(nums, count) ? "true" : "false");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -41,7 +74,10 @@ int main(int argc, char **argv) ...@@ -41,7 +74,10 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
if (pos < i || pos >= numsSize - 1)
{
break;
}
``` ```
## 选项 ## 选项
...@@ -49,17 +85,26 @@ int main(int argc, char **argv) ...@@ -49,17 +85,26 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
if (pos < i || pos >= numsSize - 1)
{
continue;
}
``` ```
### B ### B
```cpp ```cpp
if (pos < i && pos >= numsSize - 1)
{
break;
}
``` ```
### C ### C
```cpp ```cpp
if (pos < i && pos >= numsSize - 1)
{
continue;
}
``` ```
\ No newline at end of file
...@@ -2,6 +2,79 @@ ...@@ -2,6 +2,79 @@
<p>给定一个 <code>m x n</code> 二维字符网格 <code>board</code> 和一个字符串单词 <code>word</code> 。如果 <code>word</code> 存在于网格中,返回 <code>true</code> ;否则,返回 <code>false</code> 。</p><p>单词必须按照字母顺序,通过相邻的单元格内的字母构成,其中“相邻”单元格是那些水平相邻或垂直相邻的单元格。同一个单元格内的字母不允许被重复使用。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0079.Word%20Search/images/word2.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","E"]], word = "ABCCED"<strong><br />输出:</strong>true</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0079.Word%20Search/images/word-1.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","E"]], word = "SEE"<strong><br />输出:</strong>true</pre><p><strong>示例 3:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0079.Word%20Search/images/word3.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","E"]], word = "ABCB"<strong><br />输出:</strong>false</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == board.length</code></li> <li><code>n = board[i].length</code></li> <li><code>1 <= m, n <= 6</code></li> <li><code>1 <= word.length <= 15</code></li> <li><code>board</code> 和 <code>word</code> 仅由大小写英文字母组成</li></ul><p> </p><p><strong>进阶:</strong>你可以使用搜索剪枝的技术来优化解决方案,使其在 <code>board</code> 更大的情况下可以更快解决问题?</p> <p>给定一个 <code>m x n</code> 二维字符网格 <code>board</code> 和一个字符串单词 <code>word</code> 。如果 <code>word</code> 存在于网格中,返回 <code>true</code> ;否则,返回 <code>false</code> 。</p><p>单词必须按照字母顺序,通过相邻的单元格内的字母构成,其中“相邻”单元格是那些水平相邻或垂直相邻的单元格。同一个单元格内的字母不允许被重复使用。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0079.Word%20Search/images/word2.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","E"]], word = "ABCCED"<strong><br />输出:</strong>true</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0079.Word%20Search/images/word-1.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","E"]], word = "SEE"<strong><br />输出:</strong>true</pre><p><strong>示例 3:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0079.Word%20Search/images/word3.jpg" style="width: 322px; height: 242px;" /><pre><strong>输入:</strong>board = [["A","B","C","E"],["S","F","C","S"],["A","D","E","E"]], word = "ABCB"<strong><br />输出:</strong>false</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>m == board.length</code></li> <li><code>n = board[i].length</code></li> <li><code>1 <= m, n <= 6</code></li> <li><code>1 <= word.length <= 15</code></li> <li><code>board</code> 和 <code>word</code> 仅由大小写英文字母组成</li></ul><p> </p><p><strong>进阶:</strong>你可以使用搜索剪枝的技术来优化解决方案,使其在 <code>board</code> 更大的情况下可以更快解决问题?</p>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <string.h>
static bool dfs(char *word, char **board, bool *used,
int row, int col, int row_size, int col_size)
{
if (board[row][col] != *word)
{
return false;
}
used[row * col_size + col] = true;
if (*(word + 1) == '\0')
{
return true;
}
bool result = false;
if (row > 0 && !used[(row - 1) * col_size + col])
{
result = dfs(word + 1, board, used, row - 1, col, row_size, col_size);
}
if (!result && row < row_size - 1 && !used[(row + 1) * col_size + col])
{
result = dfs(word + 1, board, used, row + 1, col, row_size, col_size);
}
if (!result && col > 0 && !used[row * col_size + col - 1])
{
result = dfs(word + 1, board, used, row, col - 1, row_size, col_size);
}
if (!result && col < col_size - 1 && !used[row * col_size + col + 1])
{
__________________________
}
used[row * col_size + col] = false;
return result;
}
static bool exist(char **board, int boardRowSize, int boardColSize, char *word)
{
int i, j;
int len = strlen(word);
if (len > boardRowSize * boardColSize)
{
return false;
}
bool *used = malloc(boardRowSize * boardColSize);
for (i = 0; i < boardRowSize; i++)
{
for (j = 0; j < boardColSize; j++)
{
memset(used, false, boardRowSize * boardColSize);
if (dfs(word, board, used, i, j, boardRowSize, boardColSize))
{
return true;
}
}
}
return false;
}
int main(int argc, char **argv)
{
if (argc < 3)
{
fprintf(stderr, "Usage: ./test word row1 row2...\n");
exit(-1);
}
printf("%s\n", exist(argv + 2, argc - 2, strlen(argv[2]), argv[1]) ? "true" : "false");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -78,7 +151,7 @@ int main(int argc, char **argv) ...@@ -78,7 +151,7 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
result = dfs(word + 1, board, used, row, col + 1, row_size, col_size);
``` ```
## 选项 ## 选项
...@@ -86,17 +159,17 @@ int main(int argc, char **argv) ...@@ -86,17 +159,17 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
result = dfs(word - 1, board, used, row, col + 1, row_size, col_size);
``` ```
### B ### B
```cpp ```cpp
result = dfs(word + 1, board, used, row, col - 1, row_size, col_size);
``` ```
### C ### C
```cpp ```cpp
result = dfs(word - 1, board, used, row, col - 1, row_size, col_size);
``` ```
\ No newline at end of file
...@@ -36,6 +36,47 @@ ...@@ -36,6 +36,47 @@
</ul> </ul>
</div> </div>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
struct TreeNode
{
int val;
TreeNode *left;
TreeNode *right;
TreeNode() : val(0), left(nullptr), right(nullptr) {}
TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
};
class Solution
{
public:
bool isValidBST(TreeNode *root)
{
stack<TreeNode *> stk;
int prev = INT_MIN;
bool first = true;
while (!stk.empty() || root != nullptr)
{
if (root != nullptr)
{
stk.push(root);
root = root->left;
}
else
{
root = stk.top();
stk.pop();
_______________________
}
}
return true;
}
};
```
## template ## template
```cpp ```cpp
...@@ -86,7 +127,13 @@ public: ...@@ -86,7 +127,13 @@ public:
## 答案 ## 答案
```cpp ```cpp
if (!first && prev >= root->val)
{
return false;
}
first = false;
prev = root->val;
root = root->right;
``` ```
## 选项 ## 选项
...@@ -94,17 +141,35 @@ public: ...@@ -94,17 +141,35 @@ public:
### A ### A
```cpp ```cpp
if (first && prev >= root->val)
{
return false;
}
first = false;
prev = root->val;
root = root->right;
``` ```
### B ### B
```cpp ```cpp
if (first || prev >= root->val)
{
return false;
}
first = false;
prev = root->val;
root = root->right;
``` ```
### C ### C
```cpp ```cpp
if (!first || prev >= root->val)
{
return false;
}
first = false;
prev = root->val;
root = root->right;
``` ```
\ No newline at end of file
...@@ -2,6 +2,62 @@ ...@@ -2,6 +2,62 @@
<p>存在一个按升序排列的链表,给你这个链表的头节点 <code>head</code> ,请你删除链表中所有存在数字重复情况的节点,只保留原始链表中 <strong>没有重复出现</strong><em> </em>的数字。</p><p>返回同样按升序排列的结果链表。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0082.Remove%20Duplicates%20from%20Sorted%20List%20II/images/linkedlist1.jpg" style="width: 500px; height: 142px;" /><pre><strong>输入:</strong>head = [1,2,3,3,4,4,5]<strong><br />输出:</strong>[1,2,5]</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0082.Remove%20Duplicates%20from%20Sorted%20List%20II/images/linkedlist2.jpg" style="width: 500px; height: 205px;" /><pre><strong>输入:</strong>head = [1,1,1,2,3]<strong><br />输出:</strong>[2,3]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点数目在范围 <code>[0, 300]</code> 内</li> <li><code>-100 <= Node.val <= 100</code></li> <li>题目数据保证链表已经按升序排列</li></ul> <p>存在一个按升序排列的链表,给你这个链表的头节点 <code>head</code> ,请你删除链表中所有存在数字重复情况的节点,只保留原始链表中 <strong>没有重复出现</strong><em> </em>的数字。</p><p>返回同样按升序排列的结果链表。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0082.Remove%20Duplicates%20from%20Sorted%20List%20II/images/linkedlist1.jpg" style="width: 500px; height: 142px;" /><pre><strong>输入:</strong>head = [1,2,3,3,4,4,5]<strong><br />输出:</strong>[1,2,5]</pre><p><strong>示例 2:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0082.Remove%20Duplicates%20from%20Sorted%20List%20II/images/linkedlist2.jpg" style="width: 500px; height: 205px;" /><pre><strong>输入:</strong>head = [1,1,1,2,3]<strong><br />输出:</strong>[2,3]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点数目在范围 <code>[0, 300]</code> 内</li> <li><code>-100 <= Node.val <= 100</code></li> <li>题目数据保证链表已经按升序排列</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
struct ListNode
{
int val;
struct ListNode *next;
};
struct ListNode *deleteDuplicates(struct ListNode *head)
{
struct ListNode dummy;
struct ListNode *p, *q, *prev;
prev = &dummy;
dummy.next = head;
p = q = head;
while (p != NULL)
{
_____________________
}
return dummy.next;
}
int main(int argc, char **argv)
{
int i;
struct ListNode *head = NULL;
struct ListNode *prev = NULL;
struct ListNode *p;
for (i = 0; i < argc - 1; i++)
{
p = malloc(sizeof(*p));
p->val = atoi(argv[i + 1]);
p->next = NULL;
if (head == NULL)
{
head = p;
prev = head;
}
else
{
prev->next = p;
prev = p;
}
}
p = deleteDuplicates(head);
while (p != NULL)
{
printf("%d ", p->val);
p = p->next;
}
printf("\n");
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -73,7 +129,19 @@ int main(int argc, char **argv) ...@@ -73,7 +129,19 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
while (q != NULL && q->val == p->val)
{
q = q->next;
}
if (p->next == q)
{
prev = p;
}
else
{
prev->next = q;
}
p = q;
``` ```
## 选项 ## 选项
...@@ -81,17 +149,44 @@ int main(int argc, char **argv) ...@@ -81,17 +149,44 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
while (q != NULL && q->val == p->val)
{
q = q->next;
}
if (p->next == q)
{
prev = p;
}
else
{
prev->next = q;
}
``` ```
### B ### B
```cpp ```cpp
while (q != NULL && q->val == p->val)
{
q = q->next;
}
if (p->next == q)
{
prev = p;
}
p = q;
``` ```
### C ### C
```cpp ```cpp
while (q != NULL && q->val == p->val)
{
q = q->next;
}
if (p->next == q)
{
prev->next = q;
}
p = q;
``` ```
\ No newline at end of file
...@@ -51,6 +51,52 @@ P I ...@@ -51,6 +51,52 @@ P I
</ul> </ul>
</div> </div>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
class Solution
{
public:
string convert(string s, int numRows)
{
if (numRows == 1)
return s;
int len = s.size();
if (len <= numRows)
return s;
int cycle_len = 2 * numRows - 2;
int full_cycles = len / cycle_len;
int left = len % cycle_len;
string r;
int i;
for (i = 0; i < full_cycles; ++i)
{
r += s[i * cycle_len];
}
if (left)
r += s[i * cycle_len];
for (i = 0; i < numRows - 2; ++i)
{
int j;
for (j = 0; j < full_cycles; ++j)
{
r += s[j * cycle_len + i + 1];
r += s[j * cycle_len + i + 1 + cycle_len - 2 * (i + 1)];
}
if (left)
{
_____________________
}
}
for (i = 0; i < full_cycles; ++i)
r += s[i * cycle_len + numRows - 1];
if (left >= numRows)
r += s[i * cycle_len + numRows - 1];
return r;
}
};
```
## template ## template
```cpp ```cpp
...@@ -103,7 +149,10 @@ public: ...@@ -103,7 +149,10 @@ public:
## 答案 ## 答案
```cpp ```cpp
if (j * cycle_len + i + 1 < len)
r += s[j * cycle_len + i + 1];
if (j * cycle_len + i + 1 + cycle_len - 2 * (i + 1) < len)
r += s[j * cycle_len + i + 1 + cycle_len - 2 * (i + 1)];
``` ```
## 选项 ## 选项
...@@ -111,17 +160,26 @@ public: ...@@ -111,17 +160,26 @@ public:
### A ### A
```cpp ```cpp
if (j * cycle_len + i + 1 < len)
r += s[j * cycle_len + i];
if (j * cycle_len + i + cycle_len - 2 * (i + 1) < len)
r += s[j * cycle_len + i + cycle_len - 2 * (i + 1)];
``` ```
### B ### B
```cpp ```cpp
if (j * cycle_len + i + 1 < len)
r += s[j * cycle_len + i + 1];
if (j * cycle_len + i + 1 + cycle_len - 1 * (i + 1) < len)
r += s[j * cycle_len + i + 1 + cycle_len - 1 * (i + 1)];
``` ```
### C ### C
```cpp ```cpp
if (j * cycle_len + i - 1 < len)
r += s[j * cycle_len + i + 1];
if (j * cycle_len + i - 1 + cycle_len - 1 * (i + 1) < len)
r += s[j * cycle_len + i - 1 + cycle_len - 1 * (i + 1)];
``` ```
\ No newline at end of file
...@@ -13,6 +13,51 @@ ...@@ -13,6 +13,51 @@
<p><strong>示例&nbsp;2:</strong></p> <p><strong>示例&nbsp;2:</strong></p>
<pre><strong>输入:</strong> candidates =&nbsp;[2,5,2,1,2], target =&nbsp;5,<strong><br />所求解集为:</strong>[[1,2,2],[5]]</pre> <pre><strong>输入:</strong> candidates =&nbsp;[2,5,2,1,2], target =&nbsp;5,<strong><br />所求解集为:</strong>[[1,2,2],[5]]</pre>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<int>> combinationSum2(vector<int> &candidates, int target)
{
vector<vector<int>> res;
sort(candidates.begin(), candidates.end());
dfs(candidates, 0, target, res);
return res;
}
private:
vector<int> stack;
void dfs(vector<int> &candidates, int start, int target, vector<vector<int>> &res)
{
if (target < 0)
{
return;
}
else if (target == 0)
{
res.push_back(stack);
}
else
{
int last = INT_MIN;
for (int i = start; i < candidates.size(); i++)
{
if (last != candidates[i])
{
stack.push_back(candidates[i]);
_________________________________
stack.pop_back();
}
last = candidates[i];
}
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -61,7 +106,7 @@ private: ...@@ -61,7 +106,7 @@ private:
## 答案 ## 答案
```cpp ```cpp
dfs(candidates, i + 1, target - candidates[i], res);
``` ```
## 选项 ## 选项
...@@ -69,17 +114,17 @@ private: ...@@ -69,17 +114,17 @@ private:
### A ### A
```cpp ```cpp
dfs(candidates, i - 1, target - candidates[i], res);
``` ```
### B ### B
```cpp ```cpp
dfs(candidates, i, target + candidates[i], res);
``` ```
### C ### C
```cpp ```cpp
dfs(candidates, i + 1, target + candidates[i], res);
``` ```
\ No newline at end of file
...@@ -2,6 +2,29 @@ ...@@ -2,6 +2,29 @@
<p>给你一个正整数 <code>n</code> ,生成一个包含 <code>1</code> 到 <code>n<sup>2</sup></code> 所有元素,且元素按顺时针顺序螺旋排列的 <code>n x n</code> 正方形矩阵 <code>matrix</code> 。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0059.Spiral%20Matrix%20II/images/spiraln.jpg" style="width: 242px; height: 242px;" /><pre><strong>输入:</strong>n = 3<strong><br />输出:</strong>[[1,2,3],[8,9,4],[7,6,5]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>n = 1<strong><br />输出:</strong>[[1]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= n <= 20</code></li></ul> <p>给你一个正整数 <code>n</code> ,生成一个包含 <code>1</code> 到 <code>n<sup>2</sup></code> 所有元素,且元素按顺时针顺序螺旋排列的 <code>n x n</code> 正方形矩阵 <code>matrix</code> 。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0059.Spiral%20Matrix%20II/images/spiraln.jpg" style="width: 242px; height: 242px;" /><pre><strong>输入:</strong>n = 3<strong><br />输出:</strong>[[1,2,3],[8,9,4],[7,6,5]]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>n = 1<strong><br />输出:</strong>[[1]]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>1 <= n <= 20</code></li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
vector<vector<int>> generateMatrix(int n)
{
vector<vector<int>> ans(n, vector<int>(n, 0));
int i, j = 0, time = 0, cnt = 1; //time记录第几圈
ans[0][0] = 1;
while (cnt < n * n)
{
___________________
time++;
}
return ans;
}
};
```
## template ## template
```cpp ```cpp
...@@ -12,50 +35,22 @@ class Solution ...@@ -12,50 +35,22 @@ class Solution
public: public:
vector<vector<int>> generateMatrix(int n) vector<vector<int>> generateMatrix(int n)
{ {
vector<vector<int>> matrix(n, vector<int>(n)); vector<vector<int>> ans(n, vector<int>(n, 0));
int direction = 0; int i, j = 0, time = 0, cnt = 1; //time记录第几圈
int hor_top = 0; ans[0][0] = 1;
int hor_bottom = n - 1; while (cnt < n * n)
int ver_left = 0;
int ver_right = n - 1;
int num = 0;
while (num < n * n)
{ {
switch (direction) for (i = time, j++; j < n - time && cnt < n * n; j++)
{ ans[i][j] = ++cnt;
case 0: for (j--, i++; i < n - time && cnt < n * n; i++)
for (int i = ver_left; i <= ver_right; i++) ans[i][j] = ++cnt;
{ for (i--, j--; j >= time && cnt < n * n; j--)
matrix[hor_top][i] = ++num; ans[i][j] = ++cnt;
} for (j++, i--; i > time && cnt < n * n; i--)
hor_top++; ans[i][j] = ++cnt;
break; time++;
case 1:
for (int i = hor_top; i <= hor_bottom; i++)
{
matrix[i][ver_right] = ++num;
}
ver_right--;
break;
case 2:
for (int i = ver_right; i >= ver_left; i--)
{
matrix[hor_bottom][i] = ++num;
}
hor_bottom--;
break;
case 3:
for (int i = hor_bottom; i >= hor_top; i--)
{
matrix[i][ver_left] = ++num;
}
ver_left++;
break;
}
direction++;
direction %= 4;
} }
return matrix; return ans;
} }
}; };
``` ```
...@@ -63,7 +58,14 @@ public: ...@@ -63,7 +58,14 @@ public:
## 答案 ## 答案
```cpp ```cpp
for (i = time, j++; j < n - time && cnt < n * n; j++)
ans[i][j] = ++cnt;
for (j--, i++; i < n - time && cnt < n * n; i++)
ans[i][j] = ++cnt;
for (i--, j--; j >= time && cnt < n * n; j--)
ans[i][j] = ++cnt;
for (j++, i--; i > time && cnt < n * n; i--)
ans[i][j] = ++cnt;
``` ```
## 选项 ## 选项
...@@ -71,17 +73,38 @@ public: ...@@ -71,17 +73,38 @@ public:
### A ### A
```cpp ```cpp
for (i = time, j++; j < n - time && cnt < n * n; j++)
ans[i][j] = ++cnt;
for (j--, i++; i < n - time && cnt < n * n; i++)
ans[i][j] = ++cnt;
for (i++, j--; j >= time && cnt < n * n; j--)
ans[i][j] = ++cnt;
for (j--, i++; i > time && cnt < n * n; i--)
ans[i][j] = ++cnt;
``` ```
### B ### B
```cpp ```cpp
for (i = time, j--; j < n - time && cnt < n * n; j++)
ans[i][j] = ++cnt;
for (j--, i++; i < n - time && cnt < n * n; i++)
ans[i][j] = ++cnt;
for (i--, j++; j >= time && cnt < n * n; j--)
ans[i][j] = ++cnt;
for (j++, i--; i > time && cnt < n * n; i--)
ans[i][j] = ++cnt;
``` ```
### C ### C
```cpp ```cpp
for (i = time, j++; j < n - time && cnt < n * n; j++)
ans[i][j] = ++cnt;
for (j--, i++; i < n - time && cnt < n * n; i++)
ans[i][j] = ++cnt;
for (i--, j++; j >= time && cnt < n * n; j--)
ans[i][j] = ++cnt;
for (j--, i--; i > time && cnt < n * n; i--)
ans[i][j] = ++cnt;
``` ```
\ No newline at end of file
...@@ -2,6 +2,36 @@ ...@@ -2,6 +2,36 @@
<p>给定一个链表,两两交换其中相邻的节点,并返回交换后的链表。</p><p><strong>你不能只是单纯的改变节点内部的值</strong>,而是需要实际的进行节点交换。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0024.Swap%20Nodes%20in%20Pairs/images/swap_ex1.jpg" style="width: 422px; height: 222px;" /><pre><strong>输入:</strong>head = [1,2,3,4]<strong><br />输出:</strong>[2,1,4,3]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = []<strong><br />输出:</strong>[]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>head = [1]<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点的数目在范围 <code>[0, 100]</code> 内</li> <li><code>0 <= Node.val <= 100</code></li></ul><p> </p><p><strong>进阶:</strong>你能在不修改链表节点值的情况下解决这个问题吗?(也就是说,仅修改节点本身。)</p> <p>给定一个链表,两两交换其中相邻的节点,并返回交换后的链表。</p><p><strong>你不能只是单纯的改变节点内部的值</strong>,而是需要实际的进行节点交换。</p><p> </p><p><strong>示例 1:</strong></p><img alt="" src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/solution/0000-0099/0024.Swap%20Nodes%20in%20Pairs/images/swap_ex1.jpg" style="width: 422px; height: 222px;" /><pre><strong>输入:</strong>head = [1,2,3,4]<strong><br />输出:</strong>[2,1,4,3]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>head = []<strong><br />输出:</strong>[]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>head = [1]<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li>链表中节点的数目在范围 <code>[0, 100]</code> 内</li> <li><code>0 <= Node.val <= 100</code></li></ul><p> </p><p><strong>进阶:</strong>你能在不修改链表节点值的情况下解决这个问题吗?(也就是说,仅修改节点本身。)</p>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
struct ListNode
{
int val;
ListNode *next;
ListNode() : val(0), next(nullptr) {}
ListNode(int x) : val(x), next(nullptr) {}
ListNode(int x, ListNode *next) : val(x), next(next) {}
};
class Solution
{
public:
ListNode *swapPairs(ListNode *head)
{
struct ListNode dummy, *prev = &dummy, *p = head;
dummy.next = head;
while (p != nullptr && p->next != nullptr)
{
struct ListNode *q = p->next;
_____________________
}
return dummy.next;
}
};
```
## template ## template
```cpp ```cpp
...@@ -39,7 +69,11 @@ public: ...@@ -39,7 +69,11 @@ public:
## 答案 ## 答案
```cpp ```cpp
p->next = q->next;
q->next = prev->next;
prev->next = q;
prev = p;
p = p->next;
``` ```
## 选项 ## 选项
...@@ -47,17 +81,29 @@ public: ...@@ -47,17 +81,29 @@ public:
### A ### A
```cpp ```cpp
q->next = prev->next;
p->next = q->next;
prev->next = q;
prev = p;
p = p->next;
``` ```
### B ### B
```cpp ```cpp
prev->next = q;
p->next = q->next;
q->next = prev->next;
prev = p;
p = p->next;
``` ```
### C ### C
```cpp ```cpp
p->next = q->next;
prev->next = q;
prev = p;
q->next = prev->next;
p = p->next;
``` ```
\ No newline at end of file
...@@ -2,6 +2,41 @@ ...@@ -2,6 +2,41 @@
<p>给定一个包含红色、白色和蓝色,一共 <code>n</code><em> </em>个元素的数组,<strong><a href="https://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95" target="_blank">原地</a></strong>对它们进行排序,使得相同颜色的元素相邻,并按照红色、白色、蓝色顺序排列。</p><p>此题中,我们使用整数 <code>0</code>、 <code>1</code><code>2</code> 分别表示红色、白色和蓝色。</p><ul></ul><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [2,0,2,1,1,0]<strong><br />输出:</strong>[0,0,1,1,2,2]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [2,0,1]<strong><br />输出:</strong>[0,1,2]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>nums = [0]<strong><br />输出:</strong>[0]</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>nums = [1]<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>n == nums.length</code></li> <li><code>1 <= n <= 300</code></li> <li><code>nums[i]</code><code>0</code><code>1</code><code>2</code></li></ul><p> </p><p><strong>进阶:</strong></p><ul> <li>你可以不使用代码库中的排序函数来解决这道题吗?</li> <li>你能想出一个仅使用常数空间的一趟扫描算法吗?</li></ul> <p>给定一个包含红色、白色和蓝色,一共 <code>n</code><em> </em>个元素的数组,<strong><a href="https://baike.baidu.com/item/%E5%8E%9F%E5%9C%B0%E7%AE%97%E6%B3%95" target="_blank">原地</a></strong>对它们进行排序,使得相同颜色的元素相邻,并按照红色、白色、蓝色顺序排列。</p><p>此题中,我们使用整数 <code>0</code>、 <code>1</code><code>2</code> 分别表示红色、白色和蓝色。</p><ul></ul><p> </p><p><strong>示例 1:</strong></p><pre><strong>输入:</strong>nums = [2,0,2,1,1,0]<strong><br />输出:</strong>[0,0,1,1,2,2]</pre><p><strong>示例 2:</strong></p><pre><strong>输入:</strong>nums = [2,0,1]<strong><br />输出:</strong>[0,1,2]</pre><p><strong>示例 3:</strong></p><pre><strong>输入:</strong>nums = [0]<strong><br />输出:</strong>[0]</pre><p><strong>示例 4:</strong></p><pre><strong>输入:</strong>nums = [1]<strong><br />输出:</strong>[1]</pre><p> </p><p><strong>提示:</strong></p><ul> <li><code>n == nums.length</code></li> <li><code>1 <= n <= 300</code></li> <li><code>nums[i]</code><code>0</code><code>1</code><code>2</code></li></ul><p> </p><p><strong>进阶:</strong></p><ul> <li>你可以不使用代码库中的排序函数来解决这道题吗?</li> <li>你能想出一个仅使用常数空间的一趟扫描算法吗?</li></ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
void sortColors(vector<int> &nums)
{
int i = 0, j = nums.size() - 1;
while (i < j)
{
if (nums[i] == 0)
{
i++;
continue;
}
if (nums[j] != 0)
{
j--;
continue;
}
swap(nums[i], nums[j]);
}
j = nums.size() - 1;
while (i < j)
{
_____________________
swap(nums[i], nums[j]);
}
}
};
```
## template ## template
```cpp ```cpp
...@@ -49,7 +84,16 @@ public: ...@@ -49,7 +84,16 @@ public:
## 答案 ## 答案
```cpp ```cpp
if (nums[i] == 1)
{
i++;
continue;
}
if (nums[j] != 1)
{
j--;
continue;
}
``` ```
## 选项 ## 选项
...@@ -57,17 +101,44 @@ public: ...@@ -57,17 +101,44 @@ public:
### A ### A
```cpp ```cpp
if (nums[i] != 1)
{
i++;
continue;
}
if (nums[j] == 1)
{
j--;
continue;
}
``` ```
### B ### B
```cpp ```cpp
if (nums[i] == 1)
{
i++;
break;
}
if (nums[j] != 1)
{
j--;
break;
}
``` ```
### C ### C
```cpp ```cpp
if (nums[i] != 1)
{
i++;
break;
}
if (nums[j] == 1)
{
j--;
break;
}
``` ```
\ No newline at end of file
...@@ -24,6 +24,90 @@ ...@@ -24,6 +24,90 @@
<li><code>obstacleGrid[i][j]</code><code>0</code><code>1</code></li> <li><code>obstacleGrid[i][j]</code><code>0</code><code>1</code></li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <stdio.h>
#include <stdlib.h>
static int uniquePathsWithObstacles(int **obstacleGrid, int obstacleGridRowSize, int obstacleGridColSize)
{
int row, col;
int reset = 0;
for (row = 0; row < obstacleGridRowSize; row++)
{
if (reset)
{
obstacleGrid[row][0] = 1;
}
else
{
if (obstacleGrid[row][0] == 1)
{
reset = 1;
}
}
}
reset = 0;
for (col = 0; col < obstacleGridColSize; col++)
{
if (reset)
{
obstacleGrid[0][col] = 1;
}
else
{
if (obstacleGrid[0][col] == 1)
{
reset = 1;
}
}
}
for (row = 0; row < obstacleGridRowSize; row++)
{
int *line = obstacleGrid[row];
for (col = 0; col < obstacleGridColSize; col++)
{
line[col] ^= 1;
}
}
for (row = 1; row < obstacleGridRowSize; row++)
{
int *last_line = obstacleGrid[row - 1];
int *line = obstacleGrid[row];
for (col = 1; col < obstacleGridColSize; col++)
{
________________________
}
}
return obstacleGrid[obstacleGridRowSize - 1][obstacleGridColSize - 1];
}
int main(int argc, char **argv)
{
if (argc < 3)
{
fprintf(stderr, "Usage: ./test m n\n");
exit(-1);
}
int i, j, k = 3;
int row_size = atoi(argv[1]);
int col_size = atoi(argv[2]);
int **grids = malloc(row_size * sizeof(int *));
for (i = 0; i < row_size; i++)
{
grids[i] = malloc(col_size * sizeof(int));
int *line = grids[i];
for (j = 0; j < col_size; j++)
{
line[j] = atoi(argv[k++]);
printf("%d ", line[j]);
}
printf("\n");
}
printf("%d\n", uniquePathsWithObstacles(grids, row_size, col_size));
return 0;
}
```
## template ## template
```cpp ```cpp
...@@ -114,7 +198,10 @@ int main(int argc, char **argv) ...@@ -114,7 +198,10 @@ int main(int argc, char **argv)
## 答案 ## 答案
```cpp ```cpp
if (line[col] != 0)
{
line[col] = line[col - 1] + last_line[col];
}
``` ```
## 选项 ## 选项
...@@ -122,17 +209,26 @@ int main(int argc, char **argv) ...@@ -122,17 +209,26 @@ int main(int argc, char **argv)
### A ### A
```cpp ```cpp
if (line[col] == 0)
{
line[col] = line[col - 1] + last_line[col];
}
``` ```
### B ### B
```cpp ```cpp
if (line[col] != 0)
{
line[col] = line[col + 1] + last_line[col];
}
``` ```
### C ### C
```cpp ```cpp
if (line[col] == 0)
{
line[col] = line[col + 1] + last_line[col];
}
``` ```
\ No newline at end of file
...@@ -49,6 +49,70 @@ ...@@ -49,6 +49,70 @@
<li><code>board[i][j]</code> 是一位数字或者 <code>'.'</code></li> <li><code>board[i][j]</code> 是一位数字或者 <code>'.'</code></li>
</ul> </ul>
以下程序实现了这一功能,请你填补空白处内容:
```cpp
#include <bits/stdc++.h>
using namespace std;
class Solution
{
public:
bool isValidSudoku(vector<vector<char>> &board)
{
for (int i = 0; i < board.size(); i++)
{
vector<bool> mark(10);
for (int j = 0; j < board.size(); j++)
{
if (!valid(board, mark, i, j))
{
return false;
}
}
}
for (int j = 0; j < board.size(); j++)
{
vector<bool> mark(10);
for (int i = 0; i < board.size(); i++)
{
if (!valid(board, mark, i, j))
{
return false;
}
}
}
for (int k = 0; k < board.size(); k++)
{
int sr = k / 3 * 3;
int sc = (k % 3) * 3;
vector<bool> mark(10);
for (int i = sr; i < sr + 3; i++)
{
________________________
}
}
return true;
}
private:
bool valid(vector<vector<char>> &board, vector<bool> &mark, int i, int j)
{
if (board[i][j] != '.')
{
int index = board[i][j] - '0';
if (mark[index])
{
return false;
}
else
{
mark[index] = 1;
}
}
return true;
}
};
```
## template ## template
```cpp ```cpp
...@@ -122,7 +186,13 @@ private: ...@@ -122,7 +186,13 @@ private:
## 答案 ## 答案
```cpp ```cpp
for (int j = sc; j < sc + 3; j++)
{
if (!valid(board, mark, i, j))
{
return false;
}
}
``` ```
## 选项 ## 选项
...@@ -130,17 +200,35 @@ private: ...@@ -130,17 +200,35 @@ private:
### A ### A
```cpp ```cpp
for (int j = sc; j < sc; j++)
{
if (!valid(board, mark, i, j))
{
return false;
}
}
``` ```
### B ### B
```cpp ```cpp
for (int j = sc; j < sc + 3; j++)
{
if (valid(board, mark, i, j))
{
return false;
}
}
``` ```
### C ### C
```cpp ```cpp
for (int j = sc; j < sc; j++)
{
if (valid(board, mark, i, j))
{
return false;
}
}
``` ```
\ No newline at end of file
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