#include<bits/stdc++.h>
#include<iostream>
#include<stdio.h>
using namespace std;
#define rep(i,n) for(int i=0; i<(n); ++i)
typedef long long ll;
#define rALL(a) (a).rbegin(),(a).rend()



int main(){
  string s; cin >> s;
  sort(rALL(s));
  bool flag = true;
  if(s[0]!='0' && s[1]=='0') flag = false;
  for(int i=1;i<s.size()-1;i++){
    if(s[i]!=s[i+1]){
      char tmp=s[i];
      s[i] = s[i+1];
      s[i+1] = tmp;
      break;
    }
    if(i==s.size()-2) flag = false;
  }
  if(s[0] == '0') false;
  
  if(flag) cout << s << endl;
  else cout << -1 << endl;
  
  return 0;
}