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

int main() {
	string S, T;
	cin >> S;
	T = S;
	sort(T.begin(), T.end(), greater<char>());
	for (int i = 0; i < S.size(); i++) {
		if (S[i] != T[i]) {
			for (int j = S.size() - 1; j > i; j--) {
				if (S[j] == T[i]) {
					swap(S[i], S[j]);
					cout << S << endl;
					return 0;
				}
			}
		}
	}
	cout << S << endl;
}