#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
a.sort()
minabs = sys.maxint
for i in range(len(a)-1):
    b = a[i+1]-a[i]
    if (b<0): break;
    if (minabs>b): minabs = b
print minabs