What are the differences between stacks and queues?

What are the differences between stacks and queues?

Stacks and queues are both data structures used to store collections of items, but they operate differently. A stack follows the Last In First Out (LIFO) principle, meaning the last item added is the first one to be removed. A queue, on the other hand, follows the First In First Out (FIFO) principle, where the first item added is the first one to be removed.

Can you give me examples of where I might use each?

Sure! Stacks are often used in scenarios like undo mechanisms in text editors or for parsing expressions. Queues are commonly used in scenarios like managing tasks in a printer queue or handling requests in a web server.

What are the main operations for each data structure?

For stacks, the main operations are push (to add an item) and pop (to remove the top item). For queues, the main operations are enqueue (to add an item to the back) and dequeue (to remove an item from the front).

Which one is more efficient in terms of memory usage?

Both stacks and queues can be implemented using arrays or linked lists, so their memory efficiency largely depends on the implementation. However, in general, they have similar memory usage characteristics.