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
bhushangawde: 2016-05-18 08:26:26

did first using o(n^2)....time limit exceeded ! :( now realised have to use merge sort

ranjanakash166: 2016-05-16 12:08:59

did using modified merge_sort ..can anybody tell me how to implement using BIT???

aspro: 2016-05-13 13:43:35

a very nice question with the use of BIT...(use long long)

atif_11: 2016-05-13 10:56:39

solved by Merge Sort in 1st go :) But i want to solve it using BIT. Pls :( give me some hints to think about BIT for this problem

ragwave: 2016-05-12 21:43:24

use unsigned long long int for counting inversions.

shan2new: 2016-04-28 02:43:41

Modification of Merge Sort. Did the same question from CLRS :)

sahilagg06: 2016-04-17 10:43:09

Read BIT from ch2 of "CP by Steven Halim" and it will be a piece of cake. :)

pablod_bc: 2016-03-18 05:32:48

Last edit: 2016-03-19 12:07:28
arthur: 2016-02-27 13:10:49

Can be solved using segment, BIT, range trees. Also try and solve LIS using segment trees. All solutions should be O(nlgn)

Devashish Mathur: 2016-02-16 06:47:14

Cheated.. but Loved it..


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