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