Stack:
The Last-In-First-Out (LIFO) principle is used by an abstract data type called a stack. The principle of "last in, first out" applies, which means that the piece that was most recently introduced is the one that is removed first.
Only one end of the stack—the "top" of the stack—is altered by the addition and removal of elements.
Pushing an element up to the top of the stack is done using a stack, and popping an element from the top of the stack is done using a stack.
The handling of function calls, backtracking, expression evaluation, and depth-first search algorithms all frequently involve stacks.
Queue:
First-In-First-Out (FIFO) is a generalized data type that is used to describe queues. The first element inserted is the first one withdrawn, according to the principle of "first in, first out" operation.
The "rear" or "back" of the line, sometimes referred to as the queue, receives elements while the "front" of the line, also known as the line, has elements removed.
Enqueue (the act of adding an element to the back of the queue) and dequeue (the act of taking the element in front of it out of the queue) are operations that are done on queues.
Algorithms that use queues frequently include those that handle requests, schedule, buffer, and do breadth-first search.
Here's a table summarizing the differences between stacks and queues:
| Feature | Stack | Queue |
|---|---|---|
| Operation | Push (add to top) and Pop (remove from top) | Enqueue (add to rear) and Dequeue (remove from front) |
| Order | LIFO (Last-In-First-Out) | FIFO (First-In-First-Out) |
| Access | Only the top element can be accessed | Elements can be accessed at both ends |
| Usage | Depth-first search, backtracking, expression evaluation, function call management | Breadth-first search, scheduling, buffering, request handling |
Both stacks and queues have their unique characteristics and are suitable for different scenarios based on the desired data organization and access patterns. Choosing between a stack and a queue depends on the specific requirements of your application or problem at hand.