Merge pull request #242 from xshahq/master

第59题

docs/Leetcode_Solutions/C++/0059._Spiral_Matrix_II.md

+# 59. Spiral Matrix II
+
+**<font color=red>难度:Medium<font>**
+
+## 刷题内容
+> 原题连接
+
+* https://leetcode.com/problems/spiral-matrix-ii/
+
+> 内容描述
+
+```
+Given a positive integer n, generate a square matrix filled with elements from 1 to n2 in spiral order.
+
+Example:
+
+Input: 3
+Output:
+[
+ [ 1, 2, 3 ],
+ [ 8, 9, 4 ],
+ [ 7, 6, 5 ]
+]
+```
+
+> 思路1
+******- 时间复杂度: O(n^2)******- 空间复杂度: O(n^2)******
+
+和之前的旋转遍历矩阵一样的方法，只不过这里我们要先分配一个矩阵储存，因为vector数组不好操作。
+
+```cpp
+class Solution {
+public:
+    vector<vector<int>> generateMatrix(int n) {
+        int temp[n][n];
+        int range = n,cur = 1;
+        for(int i = 0;i < (n + 1) / 2 ;++i)
+        {
+            for(int j = 0;j < range;++j)
+                temp[i][j + i] = cur++;
+            for(int j = 1;j < range;++j)
+                temp[i + j][i + range - 1] = cur++;
+            for(int j = 1;j < range;++j)
+                temp[i + range - 1][range + i - 1 -j] = cur++;
+            for(int j = 1;j < range - 1;++j)
+                temp[range + i - 1 - j][i] = cur++;
+            range -= 2;
+        }
+        vector<vector<int> > ans;
+        for(int i = 0;i < n;++i)
+        {
+            vector<int> v;
+            for(int j = 0;j < n;++j)
+                v.push_back(temp[i][j]);
+            ans.push_back(v);
+        }
+        return ans;
+    }
+};
+```
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