#!/bin/python

import sys


n = int(raw_input().strip())
a = map(int, raw_input().strip().split(' '))
min_step = 9999
sorted_array = sorted(a)
for i in range(n-1):
    if abs(sorted_array[i] - sorted_array[i+1]) < min_step:
        min_step = abs(sorted_array[i] - sorted_array[i+1])
print min_step