#include <stdio.h>

 #include <string.h>

 int map[][],vis[];

 int ans,n,k;

 void dfs(int row,int cnt)

 {

     if (k==cnt)

     {

         ans++;

         return ;

     }

     if (row > n)

         return ;

     for (int i = ; i <= n; i ++)

     {

         if (map[row][i] && !vis[i])

         {

             vis[i] = ;

             dfs(row+,cnt+);

             vis[i] = ;

         }

     }

     dfs(row+,cnt);//处理k<n的情况

     return ;

 }

 int main()

 {

     while(~scanf("%d%d%*c",&n,&k))

     {

         if (n==-&&k==-)

             break;

         char ch;

         ans = ;

         memset(map,,sizeof(map));

         memset(vis,,sizeof(vis));

         for (int i = ; i <= n; i ++)

         {

             for (int j = ; j <= n; j ++)

             {

                 scanf("%c",&ch);

                 if (ch=='#')

                     map[i][j] = ;

             }

             getchar();

         }

         dfs(,);

         printf("%d\n",ans);

     }

     return ;

 }