top_three = [0, 0, 0]

def insert(calories):
    top_three.sort()
    if calories > top_three[0]:
        top_three.pop(0)
        top_three.append(calories)

with open("input.txt", "r") as f:
    count = 0
    for line in f.readlines():
        try:
            count += int(line)
        except:
            insert(count)
            count = 0
    insert(count)

print(top_three[0] + top_three[1] + top_three[2])