n = int(input())

x_lst = sorted(list(map(int, input().split(' '))))

MAX_NUMBER = 1000001
min_length = MAX_NUMBER
for i in range(n-1):
    x_i = x_lst[i]
    x_j = x_lst[i+1]
    if x_i == x_j:
        continue

    d = abs(x_i-x_j)

    if d < min_length:
        min_length = d


if min_length == MAX_NUMBER:
    print(0)
else:
    print(min_length)