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
baadshah_: 2016-06-22 15:18:30

Don't use STL set (gives TLE) use MergeSort

mkfeuhrer: 2016-06-21 22:43:19

CLRS rocks :-) AC in one go !

ov3rk1ll: 2016-06-14 20:01:23

inversions are hidden in mergesort

manish3749: 2016-06-11 09:57:54

just make everything long long and leave a line after each test case by ur own

chakkriii: 2016-06-01 11:21:19

use long long for no.of inversions counter (else it would result WA)

Mallika Agarwal: 2016-05-22 16:15:21

Can an admin please help me out with some test cases on which problem is not working?
Edit - Resolved now.

Last edit: 2016-05-23 00:35:43
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


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