#include <iostream>

using namespace std;

int main(){
    string s;
    cin>>s;
    char maxnum ='0';
    char minnum ='9';
    int maxp=0;

    for(int i=0;i<s.length();i++){
        if(maxnum<=s[i]&&minnum<s[i]){
            maxnum=s[i];
            maxp=i;
        }
        minnum=min(minnum,s[i]);
    }

    for(int i=0; i<s.length(); i++){
        if(s[i]<maxnum){
            char tmp=s[i];
            s[i]=s[maxp];
            s[maxp]=tmp;break;
        }

        if(i>=maxp)break;
    }
    cout<<s;
}