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

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