Three Ninja Candidate

The Ninja squad aims to find 3 ninjas who are great collectively. Each ninja has his or her ability expressed as an integer. 3 candidates are great collectively if the product of their abilities is maximum. Given the abilities of ‘N’ ninjas in an array ARR[], find the maximum collective ability from the given pool of ninjas.

For Example :

Given N = 5,
and ARR[] = {1, 3, 5, 4, 2}
Therefore, we can see that three ninjas with ability 3,4 and 5 will give us the maximum ability and will be called great therefore the output will be 60. 

Input format :

The first line of input contains an integer T denoting the number of test cases.

The first line of each test case contains a single integer N, where ‘N’ is the array’s size.

The second line of each test case contains ‘N’ space-separated integers, denoting the elements of the array.

Output format :

For each test case, print the maximum product of abilities that can be had with given candidates.

The output of each test case will be printed in a separate line.

Constraints :

1 <= T <= 5
3 <=  N <= 3000
-500 <= ARR[i] <= 500 

Where ARR[i] is the array element at index I.

Time Limit: 1 sec

Note :

You do not need to print anything, it has already been taken care of. Just implement the given function.