fn main
[
	const n_steps := 64;
	var lines := list_break_to_lines(read_lazy(h[0]));
	const x := len(lines[0]);
	const y := len(lines);
	var a := list_to_array([x, y], list_join(lines, ""));
	var start_x := 0;
	var start_y := 0;
	for steps := 0 to n_steps do [
		var a2 := a;
		for j := 0 to y do [
			for i := 0 to x do [
				if a[i, j] = 'S' then [
					if steps = 0 then [
						start_x := i;
						start_y := j;
					]
					for d in [ [0,-1], [-1,0], [0,1], [1,0] ] do [
						var dx := d[0];
						var dy := d[1];
						if i + dx < 0 or i + dx >= x or j + dy < 0 or j + dy >= y then
							continue;
						if a[i + dx, j + dy] = '.' then
							a2[i + dx, j + dy] := 'S';
					]
				]
			]
		]
		a := a2;
	]
	var sum := 0;
	for i := 0 to x do [
		for j := 0 to y do [
			if a[i, j] = 'S' and not (i xor j xor start_x xor start_y xor n_steps) bt 0 then
				sum += 1;
		]
	]
	write(h[1], ntos(sum) + nl);
]