//No.39 桁の数字を入れ替え

import java.util.*;
import java.io.*;
import static java.util.Arrays.*;
import static java.lang.Math.*;

public class No39 {
    
    static final Scanner sc = new Scanner(System.in);
    static final PrintWriter out = new PrintWriter(System.out,false);

    static void solve() {
        int n = sc.nextInt();
        char[] cs = String.valueOf(n).toCharArray();
        int max = n;
        for (int i=0; i<cs.length; i++) {
            for (int j=i+1; j<cs.length; j++) {
                char t = cs[i]; cs[i] = cs[j]; cs[j] = t;
                max = max(max,Integer.parseInt(String.valueOf(cs)));
                t = cs[i]; cs[i] = cs[j]; cs[j] = t;
            }
        }
        out.println(max);
    }

    public static void main(String[] args) {
        long start = System.currentTimeMillis();

        solve();
        out.flush();

        long end = System.currentTimeMillis();
        //trace(end-start + "ms");
        sc.close();
    }

    static void trace(Object... o) { System.out.println(deepToString(o));}
}