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
Khairo21: 2017-04-06 14:11:47

Good Problem on Meet in the Middle Technique :)
be careful about the arrangement of the loops ;)

Last edit: 2017-04-06 14:12:02
giorgosgiapis: 2017-04-04 21:41:16

Easy one. Upper and lower bound will make your life easier!

crusader_3197: 2017-04-02 08:38:14

how do the top guys got the solution accepted in 0.02s?

sunny: 2017-04-01 12:46:06

careful about d!=0 :)

sunny: 2017-04-01 12:46:00

careful about d!=0 :)

vineetpratik: 2017-03-27 09:34:47

upper_bound, lower_bound / binary search and d!=0.

nilabja16180: 2017-03-03 10:00:47

1.85 sec, still it passes!

vladimira: 2017-02-28 02:20:46

Some hate comments bcs of TLEs =)) But I think its a good problem for two reasons: 1 - simple arithmetic formula gives so many ways of making an algorithm 2 - makes you understand how to code same thing in fastest way

cake_is_a_lie: 2017-02-15 03:14:05

So many chances to get bugs on this one SIGFPE > SIGSEGV > WAs (curse you operator %; why don't you learn some math?!), but finally AC in 0.36s; no binary search just iterating over a, b, d and some lookup tables.

I think this one's pretty fun, since there are several viable ways to solve it and it isn't directly obvious which is better.

holmesherlock: 2017-02-02 21:32:04

"d!=0" gave me too many WA


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