Max GCD Pair Problem Statement

Given an array of positive integers, determine the Greatest Common Divisor (GCD) of a pair of elements such that it is the maximum among all possible pairs in the array. The GCD of two numbers a and b is the greatest number x that divides both a and b without leaving a remainder.

Example:

Input:

arr = [1, 5, 2, 3, 4]

Output:

2

Explanation:

The maximum GCD found is 2, which is obtained from the pair (2, 4). All other pairs yield a GCD of 1.

Input:

 The first line of input contains a single integer 'T', denoting the number of test cases. Each test case includes: - An integer 'N' indicating the size of the array. - 'N' space-separated positive integers that represent the elements of the array.

Output:

 For each test case, output the maximum GCD value on a new line.

Constraints:

• 1 <= T <= 10
• 2 <= N <= 10^4
• 1 <= ARR[i] <= 10^5

Note:

No input or output functions need to be handled; implement the function to solve the problem as described.