func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int t;     cin >> t;     for (int i = 0; i < t; i++) {       int n;       string s;       cin >> n;       cin >> s;       int flag = 0;       int p = n / 2;       p = p - 1;       for (int i = 0; i <= p; i++) {         if ((abs(s[i] - s[n - 1 - i]) != 2) && (s[i] != s[n - 1 - i])) {           cout <<  NO  << endl;           flag = 1;           break;         }       }       if (flag == 1) {         continue;       }       cout <<  YES  << endl;     }     return 0;   }   