ryuji0123

import numpy as np

def countMatchedSwitch(sw_status, switch, index):
    ret = 0
    for s in switch[index]:
        if int(sw_status[int(s) - 1]) == 1:
            ret += 1
    return ret % 2

ryuji0123

# Definition for a binary tree node.
class TreeNode(object):
    def __init__(self, x):
        self.val = x
        self.left = None
        self.right = None

class Solution(object):
    def constructMaximumBinaryTree(self, nums):
        """

ryuji0123

class Stack(object):
    def __init__(self):
        self.container = []
    
    def __len__(self):
        return len(self.container)
    
    def push(self, elem):
        self.container.append(elem)
    

ryuji0123

BASE =  1000000007
 
if __name__ == '__main__':
    N, M = [int(i) for i in input().split()]
    not_available = []
    for i in range(M):
        not_available.append(int(input()))
    x = 0
    y = 1
    predicted_next = 1

ryuji0123

class Solution(object):
    def maxProfit(self, prices):
        """
        :type prices: List[int]
        :rtype: int
        """
        if len(prices) == 0:
            return 0
        max_profit = 0
        min_price = prices[0]

ryuji0123

def getDivisableCount(min_bound, max_bound, div):
    return max_bound // div - (min_bound - 1) // div

def LCM(a, b):
    return a * b // GCD(a, b)

def GCD(a, b):
    if a > b:
        a, b = b, a
    while b % a != 0:

ryuji0123

__name__ == '__main__':
    N = int(input())
    d = sorted([int(i) for i in input().split()])
    print(d[N // 2] - d[N // 2 - 1])

ryuji0123

class Solution(object):
    def maxProfit(self, prices):
        """
        :type prices: List[int]
        :rtype: int
        """
        if len(prices) == 0:
            return 0
        i = 0
        while i < len(prices) - 1:

ryuji0123

class Solution(object):
    def productExceptSelf(self, nums):
        """
        :type nums: List[int]
        :rtype: List[int]
        """
        mul = 1
        right_side_mul = []
        left_side_mul = []
        for num in reversed(nums):

ryuji0123

div = 2019
if __name__ == '__main__':
    L, R = [int(i) for i in input().split()]
    if R - L > div - 1:
        R = L + div - 1
    number_ref = [num for num in range(L, R + 1, 1)]

    min_mod = 2018
    for idx, i in enumerate(number_ref):
        for j in number_ref[idx + 1:]: