蛇形填数

 1 #include <stdio.h>
 2 #include <string.h>
 3 int a[103][103];
 4 int main()
 5 {
 6     int n;
 7     while(~scanf("%d", &n))
 8     {
 9         memset(a, 0, sizeof(a));
10         int num = 1;
11         int cnt = n * n;
12         int i = 0, j = n - 1;
13         a[0][n - 1] = 1;
14         while (num < cnt)
15         {
16             while (i + 1 < n && a[i + 1][j] == 0)//向下填数 
17                 a[++i][j] = ++num;
18             while (j - 1 >= 0 && a[i][j - 1] == 0)//向左填数 
19                 a[i][--j] = ++num;
20             while (i - 1 >= 0 && a[i - 1][j] == 0)//向上填数 
21                 a[--i][j] = ++num;
22             while (j + 1 < n && a[i][j + 1] == 0)//向右填数 
23                 a[i][++j] = ++num;
24             
25         }
26         for (int i = 0; i < n; i++)
27         {
28             for (int j = 0; j < n; j++)
29                 printf("%d ", a[i][j]);
30             puts("");
31         }
32     }
33     return 0;
34 
35 }