import java.util.Scanner;
/**
* @author lushuifa
* @version [版本号, 2022年04月01日}]
* @ClassName : HJ9
* @Description : 提取不重复的整数
*
输入:
9876673
复制
输出:
37689
*
* @since [2022-04-01]
*/
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
while (sc.hasNext()) {
String inputString = sc.nextLine();
char[] chars = inputString.toCharArray();
String output = "";
for (int i = chars.length-1; i >= 0; i--) {
if (output.indexOf(chars[i])==-1) {
output += chars[i];
}
}
System.out.println(output);
}
}
}