#!/bin/python3

import sys

absdiff = -1
n = int(input().strip())
a = list(map(int, input().strip().split(' ')))
# your code goes here
a.sort()
for i in range(1,len(a)):
    diff = abs(a[i]-a[i-1])
    if diff < absdiff or absdiff == -1:
        absdiff = diff
print(absdiff)