#include <bits/stdc++.h>
using namespace std::literals::string_literals;
using i64 = std::int_fast64_t;
using std::cout;
using std::endl;
using std::cin;

template<typename T>
std::vector<T> make_v(size_t a){return std::vector<T>(a);}

template<typename T,typename... Ts>
auto make_v(size_t a,Ts... ts){
  return std::vector<decltype(make_v<T>(ts...))>(a,make_v<T>(ts...));
}

int main() {
	std::string s; cin >> s;
	sort(begin(s), end(s)); reverse(begin(s), end(s));

	if(s.front() == s.back()) {
		printf("-1\n");
		return 0;
	}
	
	for(int i = (int)s.size() - 2; i >= 0; i--) {
		if(s[i] == s[i + 1]) continue;

		std::swap(s[i], s[i + 1]);
		break;
	}
	if(s.front() == '0') {
		printf("-1\n");
		return 0;
	}

	printf("%s\n", s.c_str());
	return 0;
}