#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
# your code goes here

def main(n,a):
    a = sorted(a)
    
    b = 'adf'
    for pair in range(0,len(a)-1):
        if abs(a[pair] - a[pair+1]) < b:
            
            b = abs(a[pair] - a[pair+1])
          
    print b
main(n,a)