func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int t, n, i, j, c;     char chr;     cin >> t;     bool first_diag, second_diag;     while (t--) {       cin >> n;       string arr[n];       vector<int> v;       c = 0;       for (i = 0; i < n; i++) cin >> arr[i];       first_diag = (arr[0][1] == arr[1][0]);       second_diag = (arr[n - 2][n - 1] == arr[n - 1][n - 2]);       if (first_diag && second_diag) {         if (arr[n - 2][n - 1] == arr[0][1]) {           c = 2;           v.push_back(1);           v.push_back(2);           v.push_back(2);           v.push_back(1);         }       } else if (first_diag) {         c = 1;         if (arr[n - 1][n - 2] == arr[0][1]) {           v.push_back(n);           v.push_back(n - 1);         } else {           v.push_back(n - 1);           v.push_back(n);         }       } else if (second_diag) {         c = 1;         if (arr[n - 1][n - 2] == arr[0][1]) {           v.push_back(1);           v.push_back(2);         } else {           v.push_back(2);           v.push_back(1);         }       } else {         c = 2;         v.push_back(1);         v.push_back(2);         if (arr[0][1] == arr[n - 2][n - 1]) {           v.push_back(n);           v.push_back(n - 1);         } else {           v.push_back(n - 1);           v.push_back(n);         }       }       cout << c <<   n ;       for (i = 0; i < c; i++) cout << v[2 * i] <<     << v[2 * i + 1] <<   n ;     }     return 0;   }   