#include <bits/stdc++.h>
using namespace std;

int main() {
  string S, T;
  cin >> S;
  sort(S.rbegin(), S.rend());
  T = S;
  prev_permutation(S.begin(), S.end());
  cout << ((S != T && S.at(0) != '0') ? S : "-1") << "\n";
}