fn main
[
	var lines := list_break_to_lines(read_lazy(h[0]));
	var coords := empty(tuple2(int, int));
	for l in lines do [
		var c := map(list_break(l, ','), ston);
		coords +<= mktuple2(c[0], c[1]);
	]
	var max_rect := 0;
	for i := 0 to len(coords) do [
		for j := i + 1 to len(coords) do [
			var xd := abs(coords[i].v1 - coords[j].v1) + 1;
			var yd := abs(coords[i].v2 - coords[j].v2) + 1;
			max_rect := max(max_rect, xd * yd);
		]
	]
	write(h[1], ntos(max_rect) + nl);
]