fn main
[
	var lines := list_break_to_lines(read_lazy(h[0]));
	const x := len(lines[0]) + 2;
	const y := len(lines) + 2;
	var a := array_fill(byte, '.', [x, y]);
	for j := 1 to y - 1 do [
		var line := lines[j - 1];
		for i := 1 to x - 1 do [
			a[i, j] := line[i - 1];
		]
	]
	var gears_attached := array_fill(0, [x, y]);
	var gears_ratio := array_fill(1, [x, y]);
	fn is_digit(i j : int) := a[i, j] >= '0' and a[i, j] <= '9';
	fn is_gear(i j : int) := a[i, j] = '*';
	for j := 1 to y - 1 do [
		for i := 1 to x - 1 do [
			if is_digit(i, j) then [
				var num : int := a[i, j] - '0';
				var si := i;
				i += 1;
				while is_digit(i, j) do [
					num := num * 10 + a[i, j] - '0';
					i += 1;
				]
				for qj := j - 1 to j + 2 do [
					for qi := si - 1 to i + 1 do [
						if is_gear(qi, qj) then [
							gears_attached[qi, qj] += 1;
							gears_ratio[qi, qj] *= num;
						]
					]
				]
			]
		]
	]
	var sum := 0;
	for j := 1 to y - 1 do [
		for i := 1 to x - 1 do [
			if gears_attached[i, j] = 2 then
				sum += gears_ratio[i, j];
		]
	]
	write(h[1], ntos(sum) + nl);
]