#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;

  vector<int> res;
  res.emplace_back(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;

      char temp = copy[i];
      copy[i] = copy[j];
      copy[j] = temp;
      res.emplace_back(stoi(copy));
    }
  }

  sort(res.begin(), res.end());
  cout << res.back() << '\n';

  return 0;
}