fn n_paths~cache(conn : array(int, [ ipower(36, 3) ]), start end : int) : int
[
	if start = end then
		return 1;
	var t := conn[start];
	var sum := 0;
	while t <> 0 do [
		var f := bsr t;
		t btr= f;
		sum += n_paths(conn, f, end);
	]
	return sum;
]

fn main
[
	var lines := list_break_to_lines(read_lazy(h[0]));
	var conn := array_fill(0, [ ipower(36, 3) ]);
	for l in lines do [
		var f := ston_base(l[ .. 3], 36);
		var tl := list_break_whitespace(l);
		var t := 0;
		for i := 1 to len(tl) do [
			t bts= ston_base(tl[i], 36);
		]
		conn[f] := t;
	]
	var start := ston_base("you", 36);
	var end := ston_base("out", 36);
	var result := n_paths(conn, start, end);
	write(h[1], ntos(result) + nl);
]