#include <iostream>
#include <cstdlib>
#include <cstring>

using namespace std;
using LL = long long;
using ULL = unsigned long long;

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

    int ans = stoi(N);
    const char *n = N.c_str();
    for (int i = 0; i < N.size() - 1; i++) {
        for (int j = i + 1; j < N.size(); j++) {
            char m[10];
            memcpy(m, n, N.size());
            char tmp = m[i];
            m[i] = m[j];
            m[j] = tmp;
            ans = max(ans, stoi(m));
        }
    }

    cout << ans << endl;
}