#include<iostream>
#include<iomanip>
#include<string>
#include<algorithm>
#include<vector>
#include<set>
#include<list>
#include<queue>
#include<math.h>
#include<bitset>
using ll = long long;
using namespace std;

int main(){
    ll max1 = 0, c1 = -1, c2 = -1;
    string s;
    cin >> s;
    vector<int> l(s.size());
    for (int i = 0; i < s.size(); i++) l[i] = (int) s[i];
    sort(l.begin(), l.end(), greater());
    for (int i = 0; i < s.size(); i++){
        if (c1 < 0 && s[i] != l[i]) c1 = i;
        if (c1 >= 0 && s[i] == l[c1]){
            c2 = i;
        }
    }
    swap(s[c1], s[c2]);
    cout << s << endl;
}