n = int(input())
x = [int(x) for x in input().split()]
x.sort()
res = 10**7
for i in range(n - 1):
  if x[i + 1] != x[i]:
    res = min(x[i + 1] - x[i], res)
if res != 10**7:
  print(res)
else:
  print(0)