#include <iostream>
using namespace std;

int main(){
   string s;
   cin >> s;
   for(int i = 0;i < s.size();i++){
      int max = s[i],p = i;
      for(int j = s.size();j >= i + 1;j--){
         if(max < s[j]){
            max = s[j];
            p = j;
         }
      }
      if(p != i){
         swap(s[i],s[p]);
         break;
      }
   }
   cout << s << endl;
}