#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
a.sort()

min_dif = a[1] - a[0]
for i in range(2, len(a)):
    if (a[i] - a[i-1]) < min_dif:
        min_dif = a[i] - a[i-1]
        
print min_dif