func_code_string: #include <bits/stdc++.h>   #define int long long int   const int INF = 1e9 + 7;   using namespace std;   const int m = 1e9 + 7;      signed main()   {    ios_base::sync_with_stdio(false);    cin.tie(0);    int t;    cin >> t;    while (t--)    {     int n;     cin >> n;     string a[n], b[n];     for (int i = 0; i < n; i++)      cin >> a[i];     for (int i = 0; i < n; i++)      cin >> b[i];     for (int j = 0; j < n; j++)     {      if (a[0][j] != b[0][j])      {       for (int i = 0; i < n; i++)       {        a[i][j] ^= 1;       }      }     }     for (int i = 1; i < n; i++)     {      for (int j = 1; j < n; j++)      {       if (a[i][j] != b[i][j])       {        for (int j = 0; j < n; j++)         a[i][j] ^= 1;       }      }     }     bool ans = true;     for (int i = 0; i < n; i++)     {      for (int j = 0; j < n; j++)       if (a[i][j] != b[i][j])       {        ans = false;        break;       }      if (ans == false)       break;     }     if (ans)      cout <<  YES n ;     else      cout <<  NO n ;    }       return 0;   }