Efficiently Merging Two Sorted Arrays with Python

Learn how to merge two sorted arrays in `Python` using an efficient approach while maintaining original array capacity.
---

Visit these links for original content and any more details, such as alternate solutions, latest updates/developments on topic, comments, revision history etc. For example, the original title of the Question was: Inserting elements within an array, with decrementing pointer?

If anything seems off to you, please feel free to write me at vlogize [AT] gmail [DOT] com.
---
Merging Two Sorted Arrays in Python: A Step-By-Step Guide

Merging two sorted arrays can often feel like a daunting task, particularly when trying to maintain efficiency and adhere to constraints such as requiring the merge to happen in reverse order or not using extra space. In this guide, we'll break down a common problem many programmers face: merging two sorted arrays into one while replacing zeros and maintaining the array's original capacity.

The Problem: Merging Two Arrays Efficiently

Consider two sorted arrays, nums1 and nums2, where we need to merge nums2 into nums1 in such a way that nums1 remains sorted. The challenges include:

nums1 has a fixed size (with extra zeros that we can replace)

We need to merge in reverse to maintain lower time complexity

We can't use temporary arrays or lists

In our case:

nums1 = [1, 2, 3, 0, 0, 0]

nums2 = [2, 5, 6]

Our goal is to have nums1 contain all the elements in a sorted manner, looking like this: nums1 = [1, 2, 2, 3, 5, 6].

The Solution: Step-by-Step Implementation

To solve this problem effectively, we can iterate over both arrays from the end towards the beginning. This approach ensures that we place the largest elements at the end of nums1, filling towards the front as we go.

Step 1: Initialize Pointers

Firstly, you need to initialize pointers to track your current position in nums1 and nums2, as well as a pointer for the combined length:

[[See Video to Reveal this Text or Code Snippet]]

Step 2: Compare and Place Elements

Next, you iteratively compare the last uninserted elements of nums1 and nums2. Depending on which is larger, place it in the correct location in nums1.

[[See Video to Reveal this Text or Code Snippet]]

Final Code

Bringing it all together, we have the following code:

[[See Video to Reveal this Text or Code Snippet]]

Conclusion

The method described above allows you to merge two sorted arrays efficiently, without exceeding pre-defined size constraints. By following this approach, you can ensure that nums1 will be sorted and contain all values from both input arrays.

This technique not only solves the merging problem but does so with optimal time complexity, making it suitable for large datasets. Happy coding!