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

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

hide comments
2020-01-17 03:14:50
AC in one go using merge sort
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
2019-11-22 22:44:54
Good one....solved using merge sort tree...segment tree???
2019-11-22 21:51:35
my first fenwick tree question :)
2019-11-10 05:27:54
Used BIT and inversions count to solve the problem.
2019-11-05 10:36:43
we can use ordered set (pb_ds) to solve this....
2019-11-03 10:56:10
Solve using Merge sort first, after that solve it with BIT (Binary indexed tree). AC in one go ;)
2019-11-01 04:44:13
input explanation is garbage , but BIT DESTROY it!!
2019-09-13 11:13:23
AC in 3 GO because of long long!
2019-09-09 08:32:00
can anyone please tell me how to solve it using segment tree....?
please knock at noonehere@gmail.com

Last edit: 2022-06-26 16:01:13
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