Find maximum value in an array by recursion
algorithm, arrays, pseudocode, search
Solution
You are using Divide and Conquer algorithm for finding the maximum element from the array. First, you are dividing the array into individual elements (divide), then you are comparing the elements (conquer). You are dividing the array using calling `findMaxHelper` recursively.
The general idea of Divide and conquer is shown in the figure:
Example:
Here `max` is same as your `findMaxHelper` function with two arguments i.e. `left` and `right`.
Check this example for more in depth understanding of the concept.
Problem
``` // Find a maximum element in the array. findMax(A) findMaxHelper(A, 0, A.length) findMaxHelper(A, left, right) if (left == right - 1) return A[left] else max1 = findMaxHelper(A, left, (right + left) / 2) max2 = findMaxHelper(A, (right + left) / 2, right) if (max1 > max2) return max1 else return max2 ``` I am having a hard time understanding what is happening in this pseudo-code. Can someone help explain what is happening at each line. I need to understand this code before I can answer the questions. I know that the function findMax calls the helper function findMaxHelper, then findMaxHelper uses recursion. Other than that, I really don't understand it.