#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
a.sort()
min_abs_diff = a[1]-a[0]
for i in range(len(a)):
    min_abs_diff = min(min_abs_diff, abs(a[i]-a[i-1]))
print min_abs_diff