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
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Achmet ibn Rashid:
20131212 16:02:28
Last edit: 20131212 16:56:11 

Bo MA:
20131017 06:30:56
Take care about two things:


P_Quantum:
20130828 09:17:26
Finally accepted..!!


Geanyous:
20130710 05:01:21
lol printing "%d" instead of "%lld" cost me an WA.. 

ErtiChris Eelmaa:
20130625 16:49:53
0.49 :)) 

Vipul Pandey:
20130619 19:48:22
got AC in the first attempt! just use merge sort with a bit modification. But a good one to learn a new thing. 

virtuazx:
20130612 09:38:08
Be careful about the typecasting and longlong stuff....It kills a lot of your time!! 

ওয়াসী (Wasi):
20130420 18:51:16
AC at first try...


Tony Stark:
20130415 16:21:46
I have to agree with mister Kent. Last edit: 20130403 13:03:25 

luccasiau:
20130415 16:21:46
Binary Indexed Trees are much more cooler than merge sort :) 
Added by:  Paranoid Android 
Date:  20100306 
Time limit:  3.599s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All except: PERL6 