Given an array arr of n elements that is first strictly increasing and then maybe strictly decreasing, find the maximum element in the array.
Note: If the array is increasing then just print the last element will be the maximum value.

Example 1:

Input: 
n = 9
arr[] = {1,15,25,45,42,21,17,12,11}
Output: 45
Explanation: Maximum element is 45.

Example 2:

Input: 
n = 5
arr[] = {1, 45, 47, 50, 5}
Output: 50
Explanation: Maximum element is 50.

Your Task:  
You don't need to read input or print anything. Your task is to complete the function findMaximum() which takes the array arr[], and n as parameters and returns an integer denoting the answer.

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

Constraints:
3 ≤ n ≤ 10⁶
1 ≤ arr_i ≤ 10⁶