#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
# your code goes here
#print a
minDiff=abs(a[1]-a[0])
#print minDiff
m=len(a)-2
for i in range(m):
	x=a[i]-a[i-1]
	x=abs(x)
	minDiff=min((minDiff,x))
print minDiff