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
manas0008: 2016-01-05 19:46:17

use long long int(better...for all variables)....and better...try using merge sort algorithm!

darkhire21: 2016-01-05 14:59:16

2nd test-case n= 5-> 2 3 8 6 1
inversion pairs are ( 2 , 1 ), (3,1) , (8 , 6) , (8 , 1) , (6 , 1) .

abhigupta4: 2015-12-29 18:04:11

For all those struggling to understand how exactly merge sort will be useful should refer this
http://www.geeksforgeeks.org/counting-inversions/

Kartik: 2015-12-26 06:55:33

keep n long long, cost me a WA

Shubham Gupta: 2015-12-18 21:20:46

Only keep the counter as long long.
Take care of the formatting,newline after the no. of testcases(t) and then after every set of numbers.

archit saxena: 2015-12-17 17:48:21

omg took 10 hours to solve use mergesort to get O(nlogn)time.bubblesort might look attractive at first but gives O(n^2)time

Sarin Nanda: 2015-12-11 15:35:28

advice : use long long instead of int
i was getting WA before that

computer science: 2015-12-09 14:30:18

nice segment tree

rocode0001: 2015-12-08 09:59:58

Stupid mistake costed 3 wrngs!!!

soltan: 2015-12-03 12:20:22

i can't understand what the judge says wrong answer on test 1 but when i run in my pc it is correct


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