#4SequencesOfEqualStrings

import java.util.Scanner;

public class SequencesOfEqualStrings {

    public static void main(String[] args) {

        Scanner scan = new Scanner(System.in);
        String[] input = (scan.nextLine()).split(" ");
        System.out.print(input[0]);

        for (int i = 1; i < input.length; i++) {

            if (input[i].equals(input[i - 1])) {

                System.out.print(" " + input[i]);

            } else {

                System.out.println();
                System.out.print(input[i]);

            }
        }
    }
}