#include <bits/stdc++.h>
using namespace std;
using ll = long long;
//const ll MOD = 1e9 + 7;
//const ll MOD = 998244353;
//const ll MOD = ;
ll mod(ll A, ll M) {return (A % M + M) % M;}
const ll INF = 1LL << 60;
template<class T> bool chmin(T& a, T b) {if (a > b) {a = b; return true;} return false;}
template<class T> bool chmax(T& a, T b) {if (a < b) {a = b; return true;} return false;}
ll divceil(ll A, ll B) {return (A + (B - 1)) / B;}
ll myctoi(char C) {return C - '0';}
char myitoc(ll N) {return '0' + N;}
#define FINALANS(A) {cout << (A) << '\n'; exit(0);}

int main()
{
  string X;
  cin >> X;

  sort(X.begin(), X.end(), greater<char>());

  for (ll i = X.size() - 2; i >= 0; i--)
  {
    if (X.at(i + 1) != X.at(i))
    {
      swap(X.at(i + 1), X.at(i));
      FINALANS((X.front() != '0') ? X : "-1");
    }
  }
  FINALANS("-1");
}