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] <= 10^7). 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
sajalagrawal14: 2019-12-03 13:46:03

Can be solved Using
1)Segment tree
2)fenwick tree (with or without cordinate compression)
3)merge sort
4)policy based data structure in c++ (vary small code, even smaller than fenwick tree)
5)Self Balancing Bst

codefresher: 2019-11-22 22:44:54

Good one....solved using merge sort tree...segment tree???

abhishak69: 2019-11-22 21:51:35

my first fenwick tree question :)

ishancosmos25: 2019-11-10 05:27:54

Used BIT and inversions count to solve the problem.

theviralv: 2019-11-05 10:36:43

we can use ordered set (pb_ds) to solve this....

gabadzeluka: 2019-11-03 10:56:10

Solve using Merge sort first, after that solve it with BIT (Binary indexed tree). AC in one go ;)

mohammadsaad: 2019-11-01 04:44:13

input explanation is garbage , but BIT DESTROY it!!

scorpy1: 2019-09-13 11:13:23

AC in 3 GO because of long long!

fardin_abir: 2019-09-09 08:32:00

can anyone please tell me how to solve it using segment tree....?
please knock at fardinabir@gmail.com

keshav_ism: 2019-08-30 13:46:30

what rubbish and confusing input method.


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