func_code_string: #include <bits/stdc++.h>   using namespace std;   int digit(int n) {     int counter = 0;     while (n != 0) {       counter++;       n /= 10;     }     return counter;   }   int main() {     int T;     cin >> T;     for (int i = 0; i < T; i++) {       int n;       cin >> n;       if (n == 1) {         cout << -1 <<   n ;       } else {         cout << 5;         for (int j = 0; j < n - 1; j++) {           cout << 7;         }         cout <<   n ;       }     }   }   