Welcome back! As we continue our exploration of data structures, our focus now turns to the versatile queue. Imagine being at your favorite coffee shop where orders are taken on a first-come, first-served basis. This process exemplifies how queues function in computer science, making them ideal for modeling scenarios such as printing documents, handling customer service requests, or managing tasks in computing. Today, we will tackle two common interview problems that utilize queues to demonstrate their practical application in solving real-world challenges.

When merging data from two different sources, we seek to alternate between each source fairly, much as traffic from two lanes merges on a highway. Cars from both lanes are expected to merge seamlessly, taking turns. In the world of data structures, we face a similar task of intertwining two queues.

Suppose you're working with two devices that send printing tasks to a shared printer. You would alternate print jobs from each device's queue to prevent one device from monopolizing the printer. This concept of combining two queues by alternating their elements is what we're implementing here.

An efficient solution adheres strictly to queue operations: enqueue (to add an element) and dequeue (to remove and fetch the front element). We interleave by performing alternating dequeue operations from each queue, and adding the results to a new one. This approach respects the FIFO nature of queues and optimizes time complexity.