update exercises

data/1.算法初阶/1.蓝桥杯/放棋子/solution.md

@@ -5,30 +5,241 @@
 ## aop
 ### before
 ```cpp
-
+#include <iostream>
+#include <cstdio>
+int N = 0;
+bool CheckStoneNum(int x[][6])
+{
+    for (int k = 0; k < 6; ++k)
+    {
+        int NumRow = 0, NumCol = 0;
+        for (int i = 0; i < 6; ++i)
+        {
+            if (x[k][i])
+                NumRow++;
+            if (x[i][k])
+                NumCol++;
+        }
+        if (NumRow != 3 || NumCol != 3)
+            return false;
+    }
+    return true;
+}
+int GetRowStoneNum(int x[][6], int r)
+{
+    int sum = 0;
+    for (int i = 0; i < 6; ++i)
+    {
+        if (x[r][i])
+            sum++;
+    }
+    return sum;
+}
+int GetColStoneNum(int x[][6], int c)
+{
+    int sum = 0;
+    for (int i = 0; i < 6; ++i)
+    {
+        if (x[i][c])
+            sum++;
+    }
+    return sum;
+}
+void show(int x[][6])
+{
+    for (int i = 0; i < 6; ++i)
+    {
+        for (int j = 0; j < 6; ++j)
+        {
+            printf("%2d", x[i][j]);
+        }
+        printf("\n");
+    }
+    printf("\n");
+}
+void f(int x[][6], int r, int c);
+void GoNext(int x[][6], int r, int c)
+{
+    if (c < 6)
+    {
+        f(x, r, c + 1);
+    }
+    else
+    {
+        f(x, r + 1, 0);
+    }
+}
 ```
 ### after
 ```cpp
-
+int main()
+{
+    int x[6][6] = {
+        {1, 0, 0, 0, 0, 0},
+        {0, 0, 1, 0, 1, 0},
+        {0, 0, 1, 1, 0, 1},
+        {0, 1, 0, 0, 1, 0},
+        {0, 0, 0, 1, 0, 0},
+        {1, 0, 1, 0, 0, 1},
+    };
+    f(x, 0, 0);
+    printf("%d\n", N);
+    return 0;
+}
 ```
 
 ## 答案
 ```cpp
-
+void f(int x[][6], int r, int c)
+{
+    if (r == 6)
+    {
+        if (CheckStoneNum(x))
+        {
+            N++;
+            show(x);
+        }
+        return;
+    }
+    if (x[r][c])
+    {
+        GoNext(x, r, c);
+        return;
+    }
+    int rr = GetRowStoneNum(x, r);
+    int cc = GetColStoneNum(x, c);
+    if (cc >= 3)
+    {
+        GoNext(x, r, c);
+    }
+    else if (rr >= 3)
+    {
+        f(x, r + 1, 0);
+    }
+    else
+    {
+        x[r][c] = 1;
+        GoNext(x, r, c);
+        x[r][c] = 0;
+        if (!(3 - rr >= 6 - c || 3 - cc >= 6 - r))
+        {
+            GoNext(x, r, c);
+        }
+    }
+}
 ```
 ## 选项
 
 ### A
 ```cpp
-
+void f(int x[][6], int r, int c)
+{
+    if (r == 6)
+    {
+        if (CheckStoneNum(x))
+        {
+            N++;
+            show(x);
+        }
+        return;
+    }
+    if (x[r][c])
+    {
+        GoNext(x, r, c);
+        return;
+    }
+    int rr = GetRowStoneNum(x, r);
+    int cc = GetColStoneNum(x, c);
+    if (cc >= 3)
+    {
+        GoNext(x, r, c);
+    }
+    else if (rr >= 3)
+    {
+        f(x, r + 1, 0);
+    }
+    else
+    {
+        x[r][c] = 1;
+        GoNext(x, r, c);
+        x[r][c] = 0;
+    }
+}
 ```
 
 ### B
 ```cpp
-
+void f(int x[][6], int r, int c)
+{
+    if (r == 6)
+    {
+        if (CheckStoneNum(x))
+        {
+            N++;
+            show(x);
+        }
+        return;
+    }
+    if (x[r][c])
+    {
+        GoNext(x, r, c);
+        return;
+    }
+    int rr = GetRowStoneNum(x, r);
+    int cc = GetColStoneNum(x, c);
+    if (cc >= 3)
+    {
+        GoNext(x, r, c);
+    }
+    else if (rr >= 3)
+    {
+        f(x, r + 1, 0);
+    }
+    else
+    {
+        if (!(3 - rr >= 6 - c || 3 - cc >= 6 - r))
+        {
+            GoNext(x, r, c);
+        }
+    }
+}
 ```
 
 ### C
 ```cpp
-
+void f(int x[][6], int r, int c)
+{
+    if (r == 6)
+    {
+        if (CheckStoneNum(x))
+        {
+            N++;
+            show(x);
+        }
+        return;
+    }
+    if (x[r][c])
+    {
+        GoNext(x, r, c);
+        return;
+    }
+    int rr = GetRowStoneNum(x, r);
+    int cc = GetColStoneNum(x, c);
+    if (cc >= 3)
+    {
+        GoNext(x, r, c);
+    }
+    else if (rr >= 3)
+    {
+        f(x, r + 1, 0);
+    }
+    else
+    {
+        x[r][c] = 0;
+        if (!(3 - rr >= 6 - c || 3 - cc >= 6 - r))
+        {
+            GoNext(x, r, c);
+        }
+    }
+}
 ```