> #include <iostream>
> #include <string.h>
> #include <stdio.h>
> #include <algorithm>
> using namespace std;
> char m[10][10];
> int cnt,n,k;
> int q[10];
> void dfs(int row,int num)
> {
> 	if(num >= k){
> 		cnt++;
> 		return ;
> 	}
> 	int i,j;
> 	for(i = row;i < n;i++){	//我下面传row，这里row+1有什么问题嘛？	
> 		for(j = 0;j < n;j++){		
> 			if(q[j] == 0 && m[i][j] != '.'){
> 				q[j] = 1;
> 				dfs(i+1,num+1);
> 				q[j] = 0;
> 			}
> 		}
> 	}
> }
> int main()
> {
> 	while(~scanf("%d%d",&n,&k)){
> 		if(n == -1 && k == -1){
> 			break;
> 		}
> 		for(int i = 0;i < n;i++){
> 			scanf("%s",m[i]);
> 		}
> 		memset(q,0,sizeof(q));
> 		cnt = 0;
> 		dfs(0,0);
> 		printf("%d\n",cnt);
> 	}
> 	return 0;
> } 
hh