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



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

hide comments
2016-11-08 23:26:41
shvkppl: binary-search is just a way to solve it, and not the most efficient one, IMHO.
2016-11-04 17:43:34
is this actually a binary-search problem?
2016-10-20 15:51:50
can some one please explain me the question by solving a testcase manually....since i didnt understand the question
2016-09-28 18:47:35
Even though unordered_map uses O(n^3) and bounds uses O(n^3logn) ,, map tle's while upper and lower bound got ac
2016-09-10 13:41:09
My 15th :P . Tricky one case when D==0
2016-09-07 10:10:50 Shivam
HashMap<Integer , Integer> times out. Any ideas why ?
2016-09-04 13:17:38 Mihir Saxena
Kept on getting a TLE repeatedly on using MAP structure, just replaced the map keyword by unordered_map all over the program, rest of the code was the same and got accepted :)
2016-08-19 17:33:01
accepted in 2nd go
--> 2 vectors for lhs nd rhs
--> 1 sort function for rhs vector
--> lower and upper for lhs in rhs
--> cout<<ub-v2.begin())-(lb-v2.begin();
2016-08-06 21:59:05
how is it happening can't understand plz help
2016-08-04 07:12:21
Map will make you get TLE. Use lower_bound and upper_bound guys. O(n^3.logn). GL
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