In this post, we will learn the difference between Stack and Queue in Java. This is a frequently asked
question in Java interviews for beginners. Let's dive into it.
question in Java interviews for beginners. Let's dive into it.
| Stack | Queue |
|---|---|
| Stack is a data structure that follows the LIFO (Last In First Out) principle. | Queue is a data structure that follows the FIFO (First In First Out) principle. |
| Insertion and removal of elements take place at the same end in a stack, referred to as the "top" of the stack. | In a queue, insertion of elements takes place at the rear end and removal occurs at the front end. |
| Stacks are mainly used in scenarios where data is required to be accessed in the reverse order it was entered, like in recursion or when implementing a backtracking algorithm. | Queues are often used in scenarios where data needs to be processed in the exact order it was entered, like in simulations of real-world queues (people queuing at a ticket booth) or in breadth-first search algorithms. |
| Stack can be implemented using an array or a linked list. | Queue can also be implemented using an array or a linked list. |
| Some standard operations on a stack include push (inserting an element), pop (removing the top element), peek, or top (checking the top element without removing it). | Some standard operations on a queue include: enqueue (inserting an element at the rear end), dequeue (removing an element from the front end), peek, or front (checking the front element without removing it). |
| A stack may result in a StackOverflow error if too many operations are performed (usually due to deep recursion). | A queue does not have this issue, although if a queue is implemented with a finite size, it can become full if too many elements are added. |
| Stack doesn't inherently support accessing other elements except the top one. | Queue inherently supports accessing all the elements from front to rear. |