import heapq
import math
n = int(input())
k = int(input())
ni = [int(input()) for i in range(n)] 
 
h = []
m = []
for i in ni:
    heapq.heappush(h, -i)
 
for i in ni:
    heapq.heappush(m, i)
 
nmax = heapq.heappop(h)
nmin = heapq.heappop(m)
print(math.ceil(-nmax - nmin))