func_code_string: #include <bits/stdc++.h>   #include <string>      using namespace std;      bool susp() {       int n;       cin >> n;       string days;       cin >> days;       for (int i = 0; i < n - 1; i++) {           for (int j = i + 1; j < n; j++) {               if (days[j] == days[i] && days[j - 1] != days[i])                   return false;           }       }       return true;   }      int main()   {       int t;       cin >> t;       bool cases[t];       for (int i = 0; i < t; i++) {           cases[i] = susp();       }       for (bool b : cases) {           if (b)               cout <<  YES  << endl;           else               cout <<  NO  << endl;       }       return 0;   }