using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

        static void Main()

        {

            List<double> numbers = Console.ReadLine()

                .Split(' ', StringSplitOptions.RemoveEmptyEntries)

                .Select(double.Parse)

                .ToList();

​

            for (int i = 0; i < numbers.Count - 1; i++)

            {

                if(numbers[i] == numbers[i + 1])

                {

                    numbers[i] = numbers[i] + numbers[i+1];

                    numbers.Remove(numbers[i+1]);

​

                    i = -1;

                }

            }

​

            Console.WriteLine(string.Join(" ", numbers));

        }

​

}