#!/bin/python

import sys

n = int(raw_input().strip())
a = sorted(map(int, raw_input().strip().split(' ')))
# your code goes here
'''
minimum = 0
for i in xrange(0,n-1):
    if abs(a[i+1] -a[i]) <= minimum:
        minimum = abs(a[i+1] - a[i])
            
print minimum
'''
print min(y-x for x,y in zip(a,a[1:]))