#!/bin/python3

import sys

n = int(input().strip())
a = list(map(int, input().strip().split(' ')))
b = set(a) # remove duplicate numbers

a_len = len(a)
b_len = len(b)

min_abs_diff = 0

if b_len < a_len: # if there are two or more equal numbers in a
    print(min_abs_diff) # the two equal numbers will cancel out yielding zero
else:
    b = sorted(list(b))
    min_abs_diff = b[1] - b[0]
    for step in range(2, n):
        diff = b[step] - b[step-1]
        if diff < min_abs_diff:
            min_abs_diff = diff
    print(min_abs_diff)