#include <bits/stdc++.h>

using namespace std;

int main()
{
    string s; cin >> s;

    int ma = 0;

    for (int i = 0; i < s.size(); ++i) {
        for (int j = 0; j < i; ++j) {
            swap(s[i], s[j]);
            ma = max(ma, stoi(s));
            swap(s[i], s[j]);
        }
    }

    cout << ma << endl;
}