#include <bits/stdc++.h>

#define show(x) cout << #x << " = " << x << endl

using namespace std;
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;

template <typename T>
ostream& operator<<(ostream& os, const vector<T>& v)
{
    os << "sz=" << v.size() << "\n[";
    for (const auto& p : v) {
        os << p << ",";
    }
    os << "]\n";
    return os;
}

template <typename S, typename T>
ostream& operator<<(ostream& os, const pair<S, T>& p)
{
    os << "(" << p.first << "," << p.second
       << ")";
    return os;
}


constexpr ll MOD = 1e9 + 7;

template <typename T>
constexpr T INF = numeric_limits<T>::max() / 100;

int main()
{
    string s;
    cin >> s;
    const int size = s.size();
    int maxi = stoi(s);
    for (ll i = 0; i < size - 1; i++) {
        for (ll j = i + 1; j < size; j++) {
            string s_cop = s;
            swap(s_cop[i], s_cop[j]);
            const int num = stoi(s_cop);
            maxi = max(maxi, num);
        }
    }
    cout << maxi << endl;
    return 0;
}