func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     int n;     cin >> n;     string ans;     string t;     for (int i = 0; i < n; i++) {       cin >> t;       if (i == 0) {         ans = t;         continue;       }       for (int j = 0; j < t.size(); j++)         if (ans[j] ==  ? )           ans[j] = t[j];         else if (ans[j] == t[j] || t[j] ==  ? )           ans[j] = ans[j];         else           ans[j] =  . ;     }     for (int i = 0; i < ans.size(); i++)       if (ans[i] ==  . )         ans[i] =  ? ;       else if (ans[i] ==  ? )         ans[i] =  a ;     ios_base::sync_with_stdio(false);     printf( %s , ans.c_str());     return 0;   }   