n = int(input())
if n < 2:
    print(0)
    exit()
x = list(map(int, input().split()))
x.sort()
min_diff = float('inf')
for i in range(1, len(x)):
    diff = x[i] - x[i-1]
    if diff == 0:
        continue
    if diff < min_diff:
        min_diff = diff
print(min_diff if min_diff != float('inf') else 0)