func_code_string: #include <bits/stdc++.h>   using namespace std;   char grid[55][55];   int T, N;   int main() {     cin >> T;     for (int QQQ = 0; QQQ < T; QQQ++) {       cin >> N;       bool works = true;       for (int i = 0; i < N; i++) cin >> grid[i];       for (int r = 0; r < N - 1; r++)         for (int c = 0; c < N - 1; c++)           if (grid[r][c] ==  1  &&               (grid[r + 1][c] ==  0  && grid[r][c + 1] ==  0 ))             works = false;       if (works)         cout <<  YES ;       else         cout <<  NO ;       cout << endl;     }     return 0;   }   