Given an array of N positive integers. The task is to find maximum value of |A[i] – A[j]| + |i – j|, where 0 <= i, j <= N – 1 and A[i], A[j] belong to the array.

Example 1:
Input :
N = 4
A[] = { 1, 2, 3, 1 }
Output :
4
Explanation:
Choose i = 0 and j = 4

Example 2:
Input :
N = 3
A[] = { 1, 1, 1 }
Output :
2

Your Task:
You don't need to read input or print anything. Your task is to complete the function maxValueOfExpression() which takes the array A[] and its size N as inputs and returns the maximum value of expression in array A[].

Expected Time Complexity: O(N)
Expected Auxiliary Space: O(1)

Constraints:
1 <= N <= 10^{5}
1 <= A[i] <= 10^{5}

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