func main()
	var N: int :: cui@input().toInt(&)
	var K: int :: cui@input().toInt(&)
	var n: []int :: #[N]int
	for i(0, N - 1)
		do n[i] :: cui@input().toInt(&)
	end for
	do n.sort()
	do cui@print("\{n[N - 1] - n[0]}\n")
end func