n = int(input())
i = list(map(int, input().split()))
iv = sorted(list(set(i)))
md = max(iv) - min(iv)
if len(iv) == 1:
    print(0)
else:
    for idx, num in enumerate(iv[1:],1):
        d = num - iv[idx-1]
        if d < md:
            md = d
    print(md)