#!/bin/python

import sys

#input
n = int(raw_input().strip())
arr = map(int, raw_input().strip().split(' '))

#sort the array O(nlogn)
arr.sort()

#define min_diff
min_diff = 99999

#search in the array O(n)
for index in range(len(arr)-1):
    diff = abs(arr[index] - arr[index+1])
    if (diff < min_diff):
        min_diff = diff

print min_diff