N = int(input())
l = list(map(int, input().split()))

l.sort()
ans = 0
j = 0
while ans == 0:
    j += 1
    try:
        ans = l[j] - l[j - 1]
    except:
        break

for i in range(N - 1):
    if l[i + 1] - l[i] != 0:
        if ans >= l[i +1] -l[i]:
            ans = l[i + 1] - l[i]
print(ans)