""" day3 """

import re
import fileinput

def match_all(pending):
    match = re.search(r'mul\(([0-9]{1,3}),([0-9]{1,3})\)',pending)
    if match:
        val = int(match[1])*int(match[2])
        print(f'span={match.span()}')
        return val + match_all(pending[match.span()[1]:])
    return 0

input = ''
for line in fileinput.input():
    input += line
print(match_all(input))