#!/bin/python3

import sys
import itertools
n = int(input().strip())
minimum = 0
index = 0
a = list(map(int, input().strip().split(' ')))
b = itertools.permutations(a,2)
min = 0
for i in b:
    if abs[i[0]-i[1]] < min:
        min = abs[i[0] - i[1]]
    else:
        pass
print(min)