#!/bin/python3

import sys


n = int(input().strip())
a = list(map(int, input().strip().split(' ')))
# your code goes here
list = [];
dif = a[n-1] - a[0];
list.append(abs(dif));

for i in range(0,n-1):
    if i <= n-2:
        dif = a[i] -a[i+1];
        list.append(abs(dif));
print(min(list));