#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <string>
#include <numeric>
#include <cstring>
#include <cmath>
#include <set>
#include <queue>
#include <stack>

const int MOD = 1e9 + 7;
const int iINF = 1000000000;
const long long int llINF = 1000000000000000000;
#define rep(i,n) for(int i=0;i<(n);i++)

using namespace std;
using ll = long long int;
using P = pair<int, int>;
using edge = struct{int to; int cost;};

int main()
{
    string N;
    cin >> N;
    int ans = stoi(N);
    rep(i, N.size())
    {
        for(int j = i + 1; j < N.size(); j++)
        {
            string tmp = N;
            swap(tmp[i], tmp[j]);
            ans = max(ans, stoi(tmp));
        }
    }

    cout << ans << endl;
    return 0;
}