Maximize value of (arr[i] – i) – (arr[j] – j) in an array

Given an array, arr[] find the maximum value of (arr[i] – i) – (arr[j] – j) where i is not equal to j. Where i and j vary from 0 to n-1 and n is size of input array arr[].

http://www.geeksforgeeks.org/maximize-value-of-arri-i-arrj-j-in-an-array/