黎耗,窝较兰研

啊这题我不会啊!!!

#include <iostream>
#include <cstring>
using namespace std;
char mp[10][10];
int n,k,sum,ans,vis[101];
void dfs(int a)
{
   if(sum == k)
   {
      ans ++;
      return;
   }
   if(a > n) return;
   for(int i = 1;i <= n;i ++)
   {
      if(mp[a][i] == '#' && vis[i] == 0)
      {
         sum ++;
         vis[i] = 1;
         dfs(a + 1);
         vis[i] = 0;
         sum --;
      }
   }
   dfs(a + 1);
}
//你猜是什么个思路
int main()
{
   ios::sync_with_stdio(0);
   cin.tie(0),cout.tie(0);
   //无法编译
   while (cin >> n >> k)
   {
      if (n == -1 && k == -1) break;
      ans = 0,sum = 0;
      memset(mp,0,sizeof(mp));//清空mp数组
      for(int i = 1;i <= n;i ++)
      {
         for(int j = 1;j <= n;j ++)
         {
            cin >> mp[i][j];
         }
      }
      dfs(0);
      cout << ans << "\n";
   }
}