n = int(input())
l = list(map(int, input().split()))
l.sort()
min = 1000000
for i in range(n-1):
    if min > l[i+1]-l[i]:
        if l[i+1]-l[i]!=0:
            min=l[i+1]-l[i]
if min == 1000000:
    min = 0
print(min)