#!/usr/bin/env python3
n = int(input())
x = sorted(map(int, input().split()))
ans = 10**9
for i in range(n - 1):
    d = abs(x[i] - x[i + 1])
    if d > 0:
        ans = min(ans, d)
if ans == 10**9:
    print(0)
else:
    print(ans)