#include <iostream>
#include <algorithm>
#include <vector>
#include <cstdlib>
#include <cstring>
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)

int main(void){
	string n;
	cin >> n;
	vector<string> ans;
	ans.push_back(n);
	for (int i = 0; i < n.size(); ++i){
		for (int j = i + 1; j < n.size(); ++j){
			string tmp = n;
			swap(tmp[i], tmp[j]);
			ans.push_back(tmp);
		}
	}
	// rep(i, ans.size()) cout << ans[i] << endl;
	sort(ans.begin(), ans.end());
	reverse(ans.begin(), ans.end());
	// rep(i, ans.size()) cout << ans[i] << endl;
	cout << ans[0] << endl;
	return 0;
}