N = int(input())
x = list(map(int,input().split()))
i = 0
min = 0
x.sort()

while i < N-1:
	r = x[i+ 1] - x[i]
	
	if i == 0 or (i > 0 and r < min) or (min == 0 and r > min):
		min = r
	i += 1
		
print(min)