Given an integer array nums of positive integers, return the average value of all even integers that are divisible by 3.
Note that the average of n elements is the sum of the n elements divided by n and rounded down to the nearest integer.
1 <= nums.length <= 10001 <= nums[i] <= 1000nums = [1,3,6,10,12,15]9nums = [1,2,4,7,10]0