#!/bin/python3

import sys

absDifList = []
j=1

n = int(input().strip())
a = list(map(int, input().strip().split(' ')))
# your code goes here
for i in range(0,n-1):
    for j in range(j,n):
        absDifList.append(abs(a[i]-a[j]))
print(min(absDifList))