fn main
[
	var lines := list_break_to_lines(read_lazy(h[0]));

	var sum := 0;
	for line in lines do [
		var list := map(list_break_whitespace(line), ston);
		var first := empty(int);
		while len_greater_than(list, 0) do [
			first := [ list[0] ] + first;
			var new_list := empty(int);
			for i := 1 to len(list) do
				new_list +<= list[i] - list[i - 1];
			list := new_list;
		]
		var val := list_fold(0, first, lambda(x y : int) [ return y - x; ]);
		sum += val;
	]
	write(h[1], ntos(sum) + nl);
]