#include <iostream>
#include <vector>
#include <string>
using namespace std;

int main() {
    int N;
    cin >> N;

    string Ns = to_string(N);
    int maxdigit = 0;
    int maxidx = -1;
    for (int i = 0; i < (int)Ns.size(); ++i) {
        if (maxdigit <= Ns[i] - '0') {
            maxdigit = Ns[i] - '0';
            maxidx = i;
        }
    }
    for (int i = 0; i < (int)Ns.size(); ++i) {
        if (Ns[i] - '0' < Ns[maxidx] - '0')
            swap(Ns[i], Ns[maxidx]);
    }

    cout << Ns << endl;
}