import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        try (Scanner scan = new Scanner(System.in)) {
            char tmp[] = scan.nextLine().toCharArray();
            int ans = Integer.parseInt(String.valueOf(tmp));
            
            for(int i=0; i<tmp.length-1; i++) {
                for(int j=i+1; j<tmp.length; j++) {
                    char left = tmp[i];
                    char right = tmp[j];
                    tmp[i] = right;
                    tmp[j] = left;
                    ans = Math.max(ans, Integer.parseInt(String.valueOf(tmp)));
                    tmp[i] = left;
                    tmp[j] = right;
                }
            }
            System.out.println(ans);
        }
    }
}