# -*- coding: utf-8 -*-

n = int(input())
x = list(map(int,input().split()))

x.sort()
minlen = 1000000000



for i in range(1,n):
    if x[i] != x[i-1]:
        minlen = min(minlen,abs(x[i]-x[i-1]))

if minlen == 1000000000:
    minlen = 0

print(minlen)