## 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 separated. 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:
221 23 1 2 4
Output:11```

## Code Examples

### #1 Code Example with Python Programming

```Code - Python Programming```

``````T = int(input())
for _ in range(T):
N = int(input())
a = sorted(list(map(int, input().split())))
result, ptr = 0, 0
for i in range(0, N):
while ptr < N - 1 and a[ptr] < 2 * a[i]:
ptr += 1
if a[i] * 2 == a[ptr]:
result += 1
a[ptr] = -1
print(result)``````
Copy The Code &

Input

cmd
2
2
1 2
3
1 2 4

Output

cmd
1
1