#include <iostream>
#include <algorithm>
using namespace std;
int nm[10];
int main(){
  string s;cin>>s;
  for(int i = 0; s.size() > i; i++){
    nm[s[i]-'0']++;
  }
  sort(s.begin(),s.end(),greater<char>());
  if(s[1] == '0'){
    cout << -1 << endl;
    return 0;
  }
  if(s[0]==s[s.size()-1]){
    cout << -1 << endl;
    return 0;
  }
  int z[2] = {-1,-1};
  for(int i = 0; 10 > i; i++){
    if(nm[i]){
      if(z[0] == -1){
        z[0] = i;
      }else if(z[1] == -1){
        z[1] = i;
        break;
      }
    }
  }
  for(int i = 1; s.size() > i; i++){
    //cout << s[i-1]-'0' << " " << z[1] << " " << s[i]-'0' << " " << z[0] << endl;
    if(s[i-1]-'0' == z[1] && s[i]-'0' == z[0]){
      swap(s[i-1],s[i]);
      break;
    }
  }
  cout << s << endl;

}