Given an array of distinct positive integers, the task is to find the maximum product of increasing subsequence of size 3, i.e., we need to find arr[i]*arr[j]*arr[k] such that arr[i] < arr[j] < arr[k] and i < j < k < n 
Examples:

Input: arr[] = {10, 11, 9, 5, 6, 1, 20}
Output: 2200                                        
Explaination: Increasing sub-sequences of size three are {10, 11, 20} => product 10*11*20 = 2200 {5,  6, 20} => product 5*6*20 = 600 Maximum product : 2200

Find the Increasing subsequence of length three with maximum product: https://www.geeksforgeeks.org/maximum-product-increasing-subsequence-size-3/