#!/usr/bin/perl
use v5.35.0;

my $sum = 0;
my $enabled = 1;
while (<>) {
	s/
		(do)\(\) |
		(don't)\(\) |
		mul\((\d{1,3}),(\d{1,3})\)
	/
		if ($1) {$enabled = 1}
		elsif ($2) {$enabled = 0}
		elsif ($enabled) {$sum += $3 * $4}
	/xge;
}
say $sum;