IITKWPCO  Create Collections
Little Feluda likes to play very much. As you know he only plays with numbers. So he is given n numbers. Now tries to group the numbers into disjoint collections each containing two numbers. He can form the collection containing two numbers iff small number in the collection is exactly half of large number.
Given n numbers, Find out how many maximum number of collections he can form ?
Input
T: number of test cases. (1 <= T <= 100).
For each test case:
First line will contain n : (1 <= n <= 100)
Then next line will contain n numbers single space seperated. Range of each number will be between 1 and 10^6.
Output
For each test case, output maximum number of collections that can be formed.
Example
Input: 2
2
1 2
3
1 2 4
Output:
1
1
hide comments
vineetpratik:
20160704 12:25:03
just take care of repetition, easy using map :) 

pvsmpraveen:
20160627 14:16:48
Never forget to .clear() something after each test case ;) 

mkfeuhrer:
20160621 23:03:55
simple hashing !! AC in 1 go :) take 10^7 size and use scanf...! 

gkr007:
20160602 16:30:05
@kp ur test case really helped ;) 

atulsinha007:
20160131 07:40:11
nice and easy one.. though 2 WA's :( 

goyal:
20150719 12:39:05
AC:) using maps 

Anmol Pandey:
20150124 23:47:37
To those getting WA or Runtime Error


N0VICE:
20140818 10:16:30
No need to think too


Akshay Kamthan:
20140817 07:27:17
wooh! AC in one go for the second time ;):P

Added by:  praveen123 
Date:  20130812 
Time limit:  1s 
Source limit:  50000B 
Memory limit:  1536MB 
Cluster:  Cube (Intel G860) 
Languages:  All 
Resource:  IITK ACA CSE online judge 