import strutils, sequtils, algorithm, future, sets
proc readint(f: File): int = f.readline.parseInt

var
  n = stdin.readint
  k = stdin.readint
  t = 0
  b = 1000

for i in 0..n-1:
  var v = stdin.readint
  t = max(t, v)
  b = min(b, v)

echo(t-b)