#include<bits/stdc++.h>
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;

int main(){
        string x;
        cin >> x;
        map<char,int> mp;
        rep(i,x.size()){
                mp[x[i]] ++;
        }
        if(mp.size() == 1){
                cout << -1 << endl;
                return 0;
        }
        if(mp.size() == 2 && mp['0'] == x.size() -1){
                cout << -1 << endl;
                return 0;
        }

        bool fi = true,se = false ;
        char s;
        for(auto p:mp){
                if(fi){ fi = false;se = true;}
                else if(se){s = p.first;break;}
        }
        mp[s] --;
        string ans = "";
        ans += s ;
        for(auto p:mp){
                rep(i,p.second){
                        ans += p.first ;
                }
        }
        reverse(ans.begin(),ans.end());
        cout << ans << endl;
        return 0;

}