func_code_string: #include <bits/stdc++.h>   using namespace std;   long long m[4], x, y, a;   signed main() {     ios::sync_with_stdio(false);     cin.tie(NULL), cout.tie(NULL);     for (long long i = 0; i < 10; ++i) {       cout << i << i << i << i << endl;       cin >> x >> y;       if (x == 1) m[a++] = i;     }     for (long long i = 0; i < 24; ++i) {       next_permutation(m, m + 4);       for (long long i = 0; i < 4; ++i) cout << m[i];       cout << endl;       cin >> x >> y;       if (x == 4) return cout << endl, 0;     }   }   