#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
  string s; cin >> s;
  int n = s.size();
  int ans = stoi(s);
  for(int i = 0; i < n; i++){
    for(int j = i+1; j < n; j++){
      int now = 0;
      swap(s[i], s[j]);
      for(int i = 0; i < n; i++){
        now += (s[i]-'0')*pow(10,n-1-i);
        ans = max(ans, now);
      }
      swap(s[i], s[j]);
    }
  }
  cout << ans << endl;
  return 0;
}