#include <iostream>
using namespace std;
int main(void) {
	string s;
	cin >> s;
	for (int i = 0; i < s.size(); ++i) {
		int n = s[i] - '0';
		int max_d = 0, pos = 0;
		for (int j = i + 1; j < s.size(); ++j) {
			int m = s[j] - '0';
			if (m >= max_d)
				max_d = m, pos = j;
		}
		if (n < max_d) {
			swap(s[i], s[pos]);
			break;
		}
	}
	cout << s << endl;
	return 0;
}