n = int(input())
a = list(map(int, input().split()))
a = sorted(a)
ans = 1000000000
for i in range(n - 1):
    if a[i + 1] - a[i] == 0:
        continue
    ans = min(ans, a[i + 1] - a[i])
if ans == 1000000000:
    ans = 0
print(ans)