func_code_string: #include <bits/stdc++.h>   using namespace std;   int solve(string second, char cur) {     if (second.size() == 1) {       return !(second[0] == cur);     }     int n = second.size();     int check = 0;     for (int i = 0; i < n / 2; i++) {       check += (second[i] == cur);     }     int check2 = 0;     for (int i = n / 2; i < n; i++) {       check2 += (second[i] == cur);     }     int a = solve(second.substr(n / 2, n / 2), cur + 1) + n / 2 - check;     int b = solve(second.substr(0, n / 2), cur + 1) + n / 2 - check2;     return min(a, b);   }   int main() {     std::ios::sync_with_stdio(false);     int T;     cin >> T;     int n;     string second;     while (T--) {       cin >> n;       cin >> second;       cout << solve(second,  a ) <<   n ;     }     return 0;   }   