Merge sort is one of the efficient sorting algorithm that applies the principle or uses divide and conquer pattern.

Merge sort is one of the efficient sorting algorithm that applies the principle or uses divide and conquer pattern.

Merge sort divides a given unsorted array into two equal halves sub arrays until the nth (last) array contains a single element. This is based on the fact that array of a single element is always sorted.

**Merging of Sorted Arrays**

The sub arrays are merged by comparison of the elements of the first array to the second, starting from the first element of both arrays. When compared, the one lesser than is pushed to a single sub array. This action is continued until all the sub arrays are sorted and merged.

merge sort visualization

We are going to use two functions to implement this algorithm viz: mergeSort function and merge function. MergeSort function will recursively divide the unsorted array into nth sub arrays as aforementioned while the merge function will act as the name implies, merging the sub arrays.

Speaking about sorting algorithms, one should always remember: there is more than one approach. Last time we talked about Insertion Sort and worked with one unsorted array. This time we’re going to try a different approach and more complicated pattern — Merge Sort. Our starter pack is two sorted arrays, our task is to combine them into one sorted array.

To describe merge sort, let’s just an analogy. Assume you have a piece of lego that you can break apart. Each sub piece has its own numbers and you keep breaking and breaking until there is one piece each other, with their own numbers.

This particular concept is identified as one of the most important concepts in software engineering, and that became a primary checkpoint for most of the top-level companies.

Understanding concepts such as algorithmic complexity and proper use of data structures will enable you to write more optimal code. I will list a few tools you will have under your tool-belt after taking a typical algorithms course.

In this post we will learn Merged Sort Algorithm in Javascript . Sorting is rearranging a set of data into a specific order such as ascending to descending for numbers, or vice versa. A sorting algorithm takes in a given array or list and outputs a sorted array or list.