func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, count = 0;     cin >> n;     char arr[n][n];     for (int i = 0; i < n; i++) {       for (int j = 0; j < n; j++) {         cin >> arr[i][j];       }     }     for (int i = 0; i < n; i++) {       for (int j = 0; j < n; j++) {         count = 0;         int a = i - 1, b = i + 1, c = j - 1, d = j + 1;         if (a >= 0 && a < n)           if (arr[a][j] ==  o ) count++;         if (b >= 0 && b < n)           if (arr[b][j] ==  o ) count++;         if (c >= 0 && c < n)           if (arr[i][c] ==  o ) count++;         if (d >= 0 && d < n)           if (arr[i][d] ==  o ) count++;         if (count & 1) return cout <<  NO  << endl, 0;       }     }     return cout <<  YES  << endl, 0;   }   