#include <bits/stdc++.h>
using namespace std;

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

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


    int n = x.size();
    if(x[0] == x[n-1] || x[1] == '0'){
        cout << -1 << endl;
        return 0;
    }

    int i;
    for(i = n-1;i >= 0;i--){
        if(x[n-1] != x[i]){
            swap(x[i], x[i+1]);
            break;
        }
    }

    cout << x << endl;
    return 0;
}