Stack Data Structure

CSL 102; Data Structures; IIIT Nagpur; Created by: Dr. Aniket Pingley

Introduction The concept of a stack has been discussed during the lectures on several occassions. It is a linear data structure that follows Last In First Out (LIFO) order for data-operations. Stack is an Abstract Data Type (ADT), commonly used in most programming languages. Similar to real-world stacks such as pile of plates, the stack data structure allows operation only from one end. The most common use of stack data structure in computers in the function call stack where memory management of input parameters, local variables, return addresses etc. is performed. During the lectures, we have seen how recursion is enabled using function call stack.

Image source: https://www.tutorialspoint.com/

Basic Operations

Following operations can be performed on a stack:

• push(): Insert element on top of all the current elements inside the stack. The newly pushed element become top of the stack.
• pop(): Remove and return the element at the top of the stack (if the stack is not empty).
• peek(): Get (return) the top data element of the stack, without removing it (if the stack is not empty).
• size(): Return the number of elements in the stack.
• isEmpty(): Return TRUE (1) if the stack is empty, otherwise return FALSE (0).
• isFull(): Return TRUE (1) if the stack is full, otherwise return FALSE (0). The MAX SIZE of the stack is set during initialization.

Animation for stack operations: https://www.cs.usfca.edu/~galles/visualization/StackArray.html

Implementation of Stack ADT

• Link to header file - HERE
• Link to implementation - HERE