import re
input = open("input").read()

regex = re.compile('mul\([0-9]{1,},[0-9]{1,}\)|don\'t\(\)|do\(\)')
results = regex.findall(input)
mul_enabled = True
total = 0
for i in results:
    print(i)
    if i == "do()":
        mul_enabled = True
        continue
    elif i == "don't()":
        mul_enabled = False
        continue

    if not mul_enabled:
        continue
    splitted = i.replace('(', ',').replace(')', ',').split(',')
    left = int(splitted[1])
    right = int(splitted[2])

    total += left * right
print(total)