Given an array of integers, find the subset of non-adjacent elements with the maximum sum. Calculate the sum of that subset. It is possible that the maximum sum is , the case when all elements are negative.

For example, given an array we have the following possible subsets. These exclude the empty subset and single element subsets which are also valid.

Subset      Sum
[-2, 3, 5]   6
[-2, 3]      1
[-2, -4]    -6
[-2, 5]      3
[1, -4]     -3
[1, 5]       6
[3, 5]       8

Our maximum subset sum is . Note that any individual element is a subset as well.

As another example, . In this case, it is best to choose no element: return .

Function Description

Complete the function in the editor below. It should return an integer representing the maximum subset sum for the given array.

maxSubsetSum has the following parameter(s):

• arr: an array of integers