#include <bits/stdc++.h>

using namespace std;

int main() {
  string s;
  cin >> s;
  int n = s.size();
  sort(s.rbegin(), s.rend());
  if (n == 1 || s[1] == '0') {
    cout << -1 << endl;
    return 0;
  }

  string tmp = s;
  for (int i = n - 2; 0 <= i; i--) {
    if (s[i] != s[i + 1]) {
      swap(s[i], s[i + 1]);
      break;
    }
  }
  if (s == tmp) {
    cout << -1 << endl;
  } else {
    cout << s << endl;
  }

  return 0;
}