n = int(input())
n_line = sorted(map(int, input().split()))

distance = 10e8
v1 = n_line[0]
for n in n_line[1:]:
    if n - v1 != 0 and n - v1 < distance:
        distance = n - v1
    v1 = n

print(0 if distance == 10e8 else distance)