#include <algorithm>
#include <iostream>
#include <string>
using namespace std;

int main() {
  string X;
  cin >> X;
  sort(X.begin(), X.end(), greater<char>());
  if (prev_permutation(X.begin(), X.end()) && X[0] != '0')
    cout << X << endl;
  else
    cout << -1 << endl;
}