using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _1._1.Sum_Adjacent_Equal_Numbers
{
    class Program
    {
        static void Main()
        {
            List<int> inputNumbers = Console.ReadLine().Split().Select(int.Parse).ToList();

            for (int i = 0; i < inputNumbers.Count - 1; i++)
            {
                if (inputNumbers[i] == inputNumbers[i + 1])
                {
                    inputNumbers[i] += inputNumbers[i + 1];
                    inputNumbers.RemoveAt(i + 1);
                    i = - 1;
                   
                }
            }
            Console.WriteLine(string.Join(" ", inputNumbers));
        }
    }
}