sdut1882n皇后问题

http://acm.sdut.edu.cn/sdutoj/problem.php?action=showproblem&problemid=1882

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 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include<math.h>
 4 int q[21][21],flag,a[21],f = 0;
 5 void dfs(int i, int n)
 6 {
 7     int j,k,p,l,m;
 8     if(f == 1)
 9     return ;
10     if(i>n)
11     {
12        for(l = 1 ; l <= n ; l++)
13         {
14             printf("%d ", a[l]);
15         }
16         printf("\n");
17         f = 1;
18     }
19     else
20     {
21         for(j = 1 ; j <= n; j++)
22         {
23             flag = 0;
24             for(k = 1 ; k < i ; k++)
25             if(a[k] == j||(abs(k-i)==abs(a[k]-j)))
26             flag = 1;
27             if(flag == 0)
28             {
29                 q[i][j] = 0;
30                 a[i] = j;
31                 dfs(i+1,n);
32                 q[i][j] = 1;
33             }
34         }
35     }
36 }
37 int main()
38 {
39     int n, i, j,p = 1,l;
40     scanf("%d", &n);
41     for(i = 1 ; i <= n ; i++)
42     for(j = 1 ; j <= n ; j++)
43     q[i][j] = 1;
44     dfs(1, n);
45     return 0;
46 }

 

posted @ 2012-07-11 10:20  _雨  阅读(162)  评论(0)  编辑  收藏  举报