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#include <cstdio>
#include <iostream>
//#include <bits/stdc++.h>
using namespace std;

int n,k;
int cnt;
char c[10][10];
bool vis[10][10];
bool cc[10];

void dfs(int x,int way){
    if(way == k){
        cnt++;
        return ;
    }
    if(x > n)
        return ;
    for(int i = 1; i <= n ; i++){
        if(c[x][i] == '#' && cc[i] == 0){
            cc[i] = 1;
            dfs(x+1,way+1);
            cc[i] = 0;
        }
    }
    dfs(x+1,way);
}

int main(){
    char chr;
    while(scanf("%d %d",&n,&k)!=EOF){
        if(n == -1 && k == -1){
            break;
        }
        cnt = 0;
        getchar();
        for(int i = 1 ; i <= n ; i++){
            for(int j = 1 ; j <= n ; j++){
                scanf("%c",&chr);
                c[i][j] = chr;
                if(chr == '#'){
                    vis[i][j] = 1;
                }
                else{
                    vis[i][j] = 0;
                }
            }
            getchar();
        }
        dfs(0,0);
        printf("%d\n",cnt);
    }
    return 0;
}