INVCNT - Inversion Count


Let A[0 ... n - 1] be an array of n distinct positive integers. If i < j and A[i] > A[j] then the pair (i, j) is called an inversion of A. Given n and an array A your task is to find the number of inversions of A.

Input

The first line contains t, the number of testcases followed by a blank space. Each of the t tests start with a number n (n ≤ 200000). Then n + 1 lines follow. In the ith line a number A[i - 1] is given (A[i - 1] ≤ 107). The (n + 1)th line is a blank space.

Output

For every test output one line giving the number of inversions of A.

Example

Input:
2

3
3
1
2

5
2
3
8
6
1


Output:
2
5

hide comments
r0bo_dart: 2015-06-13 13:35:15

HINT: Dont use vector for this problem with your custom designed insert. That will slow things out. Use array instead. Cost me 4 TLEs... phew. Else Merge Sort works nice. and yeah the long long thingy too.

rudra21: 2015-06-13 00:28:26

variation of Merge Sort algo.
output type is long long.
Thank You @ankur manchanda @Nitesh Tiwari

ruler: 2015-06-11 11:19:44

thanks @cr

satyajit tourani: 2015-06-11 08:18:34

easy after reading theory from CLRS( mergesort ) :) AC in 0.27 seconds. :D

Akash Goel: 2015-06-10 21:13:39

Couldn't AC without long long. Dunno why

Nitesh Tiwari: 2015-06-05 11:14:02

Reading these comments does help a lot.
Make sure to declare a proper count variable, other all can be fit into int.
Question is just a standard variation of merge sort.

Praveen Kulkarni: 2015-06-03 15:59:39

my 50th

hrwang_xn: 2015-06-01 17:37:57

use BIT.

scyth3r: 2015-05-27 14:21:16

@I W G T J have you considered blank lines as input?

I W G T J: 2015-05-27 09:59:18

Why WA? <snip>
can anyone please help?

Last edit: 2022-06-26 16:04:47

Added by:Paranoid Android
Date:2010-03-06
Time limit:3.599s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: PERL6