func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n;     while (cin >> n) {       if (n == 1 || n == 2)         cout <<  -1 n ;       else if (n == 3)         cout <<  210 n ;       else {         if (n % 6 == 1) {           cout <<  1 ;           for (int i = 3; i < n; i++) cout <<  0 ;           cout <<  20 n ;         }         if (n % 6 == 2) {           cout <<  1 ;           for (int i = 3; i < n - 1; i++) cout <<  0 ;           cout <<  200 n ;         }         if (n % 6 == 3) {           cout <<  1 ;           for (int i = 3; i < n - 1; i++) cout <<  0 ;           cout <<  110 n ;         }         if (n % 6 == 4) {           cout <<  1 ;           for (int i = 3; i < n; i++) cout <<  0 ;           cout <<  50 n ;         }         if (n % 6 == 5) {           cout <<  1 ;           for (int i = 3; i < n; i++) cout <<  0 ;           cout <<  80 n ;         }         if (n % 6 == 0) {           cout <<  1 ;           for (int i = 3; i < n - 1; i++) cout <<  0 ;           cout <<  170 n ;         }       }     }     return 0;   }   