func_code_string: #include <bits/stdc++.h>   using namespace std;   long long k, res, a[1111], n;   set<long long> s;   int main() {     cin >> n >> k;     for (long long i = 1; i <= sqrt(n); i++) {       if (n % i == 0) s.insert(i), s.insert(n / i);     }     for (long long i : s) {       res++;       if (res == k) {         cout << i;         return 0;       }     }     cout << -1;   }   