#include<bits/stdc++.h>

using namespace std;
using ll=long long;
#define rep2(i, a, n) for(int i = (a); i < (n); i++)
#define rep(i, n) rep2(i,0,n)

int main(){
  cin.tie(nullptr);ios_base::sync_with_stdio(false);
  string x;cin>>x;
  vector<char> vec;
  rep(i,x.size()){
    vec.push_back(x[i]);
  }
  sort(vec.begin(),vec.end());
  string shake;
  vector<int> hoge;
  do {
    shake="";
    rep(i,x.size()){
      shake+=vec[i];
    }
    if(shake[0]!='0')hoge.push_back(stoi(shake));
  }while(next_permutation(vec.begin(),vec.end()));
  if(hoge.size()!=1){
    sort(hoge.rbegin(),hoge.rend());
    cout<<hoge[1]<<endl;
  }else{
    cout<<-1<<endl;
  }
}