write a go solution for Description:
You are given an array of integers a_1,a_2,ldots,a_n. Find the maximum possible value of a_ia_ja_ka_la_t among all five indices (i,j,k,l,t) (i<j<k<l<t).

Input Format:
The input consists of multiple test cases. The first line contains an integer t (1<=t<=2*10^4) — the number of test cases. The description of the test cases follows.

The first line of each test case contains a single integer n (5<=n<=10^5) — the size of the array.

The second line of each test case contains n integers a_1,a_2,ldots,a_n (-3x10^3<=a_i<=3x10^3) — given array.

It's guaranteed that the sum of n over all test cases does not exceed 2*10^5.

Output Format:
For each test case, print one integer — the answer to the problem.

Note:
In the first test case, choosing a_1,a_2,a_3,a_4,a_5 is a best choice: (-1)*(-2)*(-3)*(-4)*(-5)=-120.

In the second test case, choosing a_1,a_2,a_3,a_5,a_6 is a best choice: (-1)*(-2)*(-3)*2*(-1)=12.

In the third test case, choosing a_1,a_2,a_3,a_4,a_5 is a best choice: (-1)*0*0*0*(-1)=0.

In the fourth test case, choosing a_1,a_2,a_3,a_4,a_6 is a best choice: (-9)*(-7)*(-5)*(-3)*1=945.. Output only the code with no comments, explanation, or additional text.