ABCDEF - ABCDEF


You are given a set S of integers between -30000 and 30000 (inclusive).

Find the total number of sextuples  that satisfy: 

 

Input

The first line contains integer N (1 ≤ N ≤ 100), the size of a set S.

Elements of S are given in the next N lines, one integer per line. Given numbers will be distinct.

Output

Output the total number of plausible sextuples.

Examples

Input:
1
1

Output:
1
Input:
2
2
3

Output:
4
Input:
2
-1
1

Output:
24
Input:
3
5
7
10

Output:
10



hide comments
avik26091998: 2017-12-01 09:12:37

lower_bound and upper-bound !!!

trijeet: 2017-10-29 23:48:44

Beware d can't be zero ! ac in 2nd go :)

aditya930: 2017-09-23 18:50:38

Nice one..lower bound and upper bound will help O(n^3) is acceptable.

pk201996: 2017-08-25 22:00:10

nice problem use unordered_map stl

aronzx: 2017-08-22 11:20:37

Hint: Use only one unordered_map.

zzuwenjie: 2017-08-19 03:48:06

use sort, AC in one go, O(3*(N^3)*logN) , but I don't know how to use hash.

hahaha42: 2017-07-07 15:38:21

use hash, AC in one go

deepu_2095: 2017-06-20 12:48:13

can anyone explain the problem clearly??

sandeep_4141: 2017-06-17 12:25:23

shit this d gives me 3 WA !!
A standard classic problem !!

sagnik_66: 2017-05-29 18:16:17

Great Problem!


Added by:Luka Kalinovcic
Date:2009-07-13
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: ERL JS-RHINO NODEJS PERL6 VB.NET
Resource:own problem