#include <algorithm>
#include <bits/stdc++.h>
#define fastIO (cin.tie(0), cout.tie(0), ios::sync_with_stdio(false))
using namespace std;

int main() {
  fastIO;

  string src;
  cin >> src;

  int ans = stoi(src);
  for (size_t i = 0; i < src.size() - 1; ++i) {
    for (size_t j = i + 1; j < src.size(); ++j) {
      string copy = src;
      swap(copy[i], copy[j]);
      ans = max(ans, stoi(copy));
    }
  }

  cout << ans << '\n';
  return 0;
}