import java.io.*; import java.util.*; public class Main{ public static void main(String[] args) throws Exception{ Scanner sc = new Scanner(System.in); while(sc.hasNextLine()){ String s = sc.nextLine(); char[] cc = s.toCharArray(); int[] count = new int[26]; for(char c : cc){ count[c - 'a'] += 1; } int minValue = Integer.MAX_VALUE; for(int i = 0; i < 26; ++i){ if(count[i] != 0 && minValue > count[i]){ minValue = count[i]; } } Set<Character> set = new HashSet<>(); for(int i = 0; i < 26; ++i){ if(count[i] == minValue){ set.add((char)('a' + i)); } } for(char c : cc){ if(!set.contains(c)){ System.out.print(c); } } System.out.println(); } } }