def sub(lst:list):
    s = lst[0]
    for l in lst[1:]:
        s-=l
    return s

input()
xs = list(set(map(int,input().split())))
len_x = len(xs)
min_distance = 0
if len_x != 1:
    xs.sort(reverse=True)
    sub_nums = [sub(xs[i:i + 2]) for i in range(len_x - 1)]
    min_distance = min(sub_nums)
print(min_distance)