import os

cals = []
with open("day1", 'r') as file:
    cals = file.read().split('\n')

number = 3
max_cals = [0 for i in range(number)]
max_cals_i = [0 for i in range(number)]

current_cals = 0
for i, cal in enumerate(cals):
    if cal == '':
        min_cal = min(max_cals)
        if current_cals > min_cal:
            max_cals_i[max_cals.index(min_cal)] = i
            max_cals[max_cals.index(min_cal)] = current_cals
        current_cals = 0
        continue

    current_cals += int(cal)

print(sum(max_cals))