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

using namespace std;

int main(){
	string str;
	cin >> str;
	vector<string>V;
	for (int i = 0; i < str.size(); i++){
		for (int j = i + 1; j < str.size(); j++){
			string to = str;
			swap(to[i], to[j]);
			V.push_back(to);
		}
	}
	V.push_back(str);
	sort(V.begin(), V.end());
	cout << V.back() << endl;

	return 0;

}