import java.util.Arrays;
import java.util.LinkedList;
import java.util.Scanner;

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