import java.util.Scanner;

public class Main {

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

	public static void swap(char[] a,int i,int j) {
		char temp = a[i];
		a[i] = a[j];
		a[j] = temp;
	}

}