import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
String line = sc.nextLine();
int[] letters = new int[26];
for (int i = 0; i < line.length(); i++) {
if (line.charAt(i) == '.') {
break;
}
if (line.charAt(i) >= 'a' && line.charAt(i) <= 'z') {
letters[line.charAt(i) - 'a']++;
}
}
for (int i = 0; i < letters.length; i++) {
if(letters[i] != 0) {
System.out.print((char)(i + 'a'));
}
}
System.out.print(".");
}
}