#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
# your code goes here
a.sort()
min_diff = abs(a[1] - a[0])
for i in range(1,n-1):
    temp = abs(a[i+1] - a[i])
    if temp < min_diff:
        min_diff = temp

print min_diff