with open("input.txt") as f:
    data = f.readlines()

elfs = []
sum = 0
for line in data:
    if line == "\n":
        elfs.append(sum)
        sum = 0
        continue
    sum += int(line.rstrip())
elfs.sort(reverse=True)
max = elfs[0] + elfs[1] + elfs[2]

print(max)