fn main
[
	var seq := read_lazy(h[0]);
	var sum := 0;
	while true do [
		var pos := list_search_substring(seq, "mul(");
		if pos = -1 then
			break;
		seq := seq[pos + 4 .. ];
		var comma := list_search(seq, ',');
		if comma <= 0 or comma > 3 then
			continue;
		var par := list_search(seq, ')');
		if par <= comma + 1 or par > comma + 4 then
			continue;
		if list_search_fn(seq[ .. comma], lambda (b : byte) [ return b < '0' or b > '9'; ]) >= 0 then
			continue;
		if list_search_fn(seq[comma + 1 .. par], lambda (b : byte) [ return b < '0' or b > '9'; ]) >= 0 then
			continue;
		var n1 := ston(seq[ .. comma]);
		var n2 := ston(seq[comma + 1 .. par]);
		sum += n1 * n2;
		seq := seq[par + 1 .. ];
	]
	write(h[1], ntos(sum) + nl);
]