Find the Maximum Element in an Array that is first increasing and then decreasing in C

In this article, we will discuss how to find the Maximum Element in an Array that is first increasing and then decreasing in C. Below are some array examples for the highest value in an array of numbers that are initially increasing and subsequently decreasing.

Examples:

Example 1:

Input: arr[] = {5, 10, 15, 12, 8, 3}

Output: 15

This example shows an array that expands initially from 5 to 15 and then lowers, with the maximum value being 15.

Example 2:

Input: arr[] = {2, 4, 6, 10, 8, 5, 3}

Output: 10

In this example, an array that increases initially from 2 to 10 and then decreases, with the maximum value being 10.

Example 3:

Input: arr[] = {1, 2, 3, 4, 5, 4, 3, 2, 1}

Output: 5

Here, we are taking several method to solve this problem. These methods are as follows:

Method 1: Linear Search

In this method, the array can be traversed while keeping track of the maximum and elements. After that, it returns the largest element.

Program:

Output:

 The maximum element is 89 

Method 2: Using the Binary Search - Recursive Solution

In this method, we find the largest member in an array that is expanding and decreasing iteratively using binary search.

The following are some ways to change the traditional binary search methodology:

• The mid element is the maximum if it is larger than both of its adjacent elements.
• We should attempt to search on the right half of the array if the mid member is smaller than its subsequent element. Decide that low equals mid plus 1. Array example: 2, 4, 6, 8, 10, 3,
• Similar to this, we should try to search on the left side if the mid element is larger than the following element. Decide that high = mid - 1. Array example: 3, 50, 10, 9, 7, 6.

Program:

Output:

 The maximum element is 50 

Explanation:

In this example, the findMaximum function use recursive binary search to identify the largest entry in the array. After that, the main function prints the maximum element, which is 50.

Method 3: Finding the largest member in an array that is expanding and decreasing iteratively using binary search.

The following changes can be made to the typical binary search method:

• The mid element is the maximum if it is larger than both of its adjacent elements.
• We should attempt to search on the right half of the array if the mid member is smaller than its subsequent element. Make low = mid + 1 as a result. Array example: 2, 4, 6, 8, 10, 3,
• Similar to this, we should try to search on the left side if the mid element is larger than the following element. Decide that high = mid - 1. Array example: 3, 50, 10, 9, 7, 6.

C++ Program:

Output:

 The maximum element is 60 

Explanation:

In this example, the maxInBitonic function finds the largest entry in a bitonic array using an iterative binary search method. After that, the main function prints the maximum element, which is 60.

Method 4: Stacking

1. In this method, make an empty stack to store the array element indices.
2. Go through the array in a left-to-right direction until we locate the most elements. As long as the element is less than or equal to the one before it, push the index of each element onto the stack.
3. When an element is discovered that is bigger than the one before it, we know that the maximum element has been found. After that, until we discover an index whose corresponding element is bigger than the current element, we can pop all the indices from the stack.
4. The highest element is the one that corresponds to the stack's final index.

C++ Program:

Output:

 The maximum element is 20