Welcome to the practical segment of our C++ programming journey! Today, we're applying the knowledge from past lessons to solve two practice problems using advanced C++ Standard Template Library (STL) structures: std::queue and std::map with custom comparison operators through class definitions.

Consider an event-driven system, like a restaurant. Orders arrive, and they must be handled in the order they were received, following the First In, First Out (FIFO) principle. This principle makes it a perfect scenario for a queue implementation in C++.

This code demonstrates the creation and operation of a Queue class, which leverages std::queue to efficiently implement a queue. The class includes methods to (add) an item, (remove) an item, check if the queue is empty, and return the queue's size. Enqueue operations add an item to the back of the queue, while dequeue operations remove an item from the front, maintaining the First In, First Out (FIFO) principle.