numbers = list(map(int, input().split()))
l = 0
r = 1
while True:
    try:
        if numbers[l] == numbers[r]:
            numbers[l] += numbers[r]
            numbers.pop(r)
        else:
            l += 1
            r += 1
    except:
        IndexError
        l = 0
        r = 1
        continue


    print(numbers)