import java.util.Arrays; import java.util.HashSet; import java.util.LinkedList; import java.util.Scanner; import java.util.Set; public class Main { public static void main(String[] args){ Scanner sc = new Scanner(System.in); char[] input = sc.next().toCharArray(); Arrays.sort(input); for(int i = input.length - 1; i >= 0; i--){ System.out.print(input[i]); } System.out.println(); } }