#!/bin/python3

import sys


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

print (min)