POJ_1321_DFS

来源：互联网发布：程序员健康指南 pdf 编辑：程序博客网时间：2024/06/05 20:56

//n皇后问题，暴力搜索即可

#include <stdio.h>

char map[11][11];
int ans;
char h[11];
char v[11];
int n,k;
void dfs(int x, int num)
{
    int i,j;
    int ii,jj;
    if(num == 0)
    {
        ans++;
        return;
    }
    for(i = x ; i < n; i++ )
    {
        if(0 == h[i])
        {
            for(j = 0 ; j < n; j++)
            {
                if(0 == v[j] && '#' == map[i][j])
                {
                    h[i] = 1;
                    v[j] = 1;

                    dfs(i+1,num-1);
                    h[i] = 0;
                    v[j] = 0;

                }
            }
        }
    }
    return ;
}

int
main()
{
    freopen("in","r",stdin);
    int i, j;
    while(scanf("%d %d",&n,&k) && n != -1)
    {
        for(i = 0; i < n; i++)
        {
            getchar();
            for(j = 0; j < n; j++)
            {
                scanf("%c",&map[i][j]);
            }
            v[i] = 0;
            h[i] = 0;
        }
        ans = 0;
        dfs(0,k);
        printf("%d/n",ans);
    }

}