What is a stack in C and how is it implemented?

Table of Contents

• Introduction
• Stack Operations
  • 1. Push
  • 2. Pop
  • 3. Peek (Top)
  • 4. IsEmpty
• Implementation of a Stack in C
  • Using Arrays
  • Using Linked Lists
• Conclusion

Introduction

A stack is a fundamental data structure that operates on a Last In, First Out (LIFO) principle, where the most recently added element is the first one to be removed. In C, stacks can be implemented using arrays or linked lists. This guide provides an overview of the stack data structure and practical implementation examples in C.

Stack Operations

A stack supports several key operations:

1. Push

Adds an element to the top of the stack.

2. Pop

Removes the element from the top of the stack.

3. Peek (Top)

Returns the element at the top of the stack without removing it.

4. IsEmpty

Checks whether the stack is empty.

Implementation of a Stack in C

Using Arrays

You can implement a stack using a static array with a variable to keep track of the top index.

Implementation Example:

Using Linked Lists

A stack can also be implemented using a singly linked list where each node contains data and a pointer to the next node.

Implementation Example:

Conclusion

Stacks in C are essential data structures that can be implemented using arrays or linked lists. Array-based stacks are straightforward and efficient but have a fixed size, while linked-list-based stacks offer dynamic sizing and flexibility but involve additional memory overhead. Understanding how to implement and use stacks effectively is crucial for managing data and solving problems efficiently in C.