#include <iostream>
#include <string>
#include <algorithm>

using namespace std;

int n;
string s;

int main(void)
{
	cin >> s;
	sort(s.rbegin(), s.rend());
	n = s.size();
	
	if(s[0] == s[n-1]){
		cout << -1 << endl;
		return 0;
	}
	for(int i = n-1; i >= 0; i--){
		if(s[i] != s[n-1]){
			swap(s[i], s[i+1]);
			break;
		}
	}
	if(s[0] == '0') cout << -1 << endl;
	else cout << s << endl;
	
	return 0;
}