#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))

a.sort()

m = a[1]-a[0]
for i in range(1,n):
    if m==0: break
    if m > a[i]-a[i-1]:
        m = a[i]-a[i-1]
        
print m