#!/bin/python

import sys


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

a.sort()
min_diff = None
for i in range(1,n):
    diff = abs(a[i] - a[i - 1])
    if not min_diff or diff < min_diff:
        min_diff = diff
    if min_diff < 1:
        break

print min_diff