#!/bin/python3

import sys

n = int(input().strip())
a = list(map(int, input().strip().split(' ')))
a.sort()
min = 9999
for i in range(n - 1):
    if abs(a[i] - a[i + 1]) < min:
            min = abs(a[i] - a[i + 1])
    if min < 1:
        break
print (min)