Data Structures and Algorithms-DSA_Linkedlist_class 7.pdf
- 1. Dr. CHETHAN CHANDRA S BASAVARADDI B.E., B.Ed., M.Tech., Ph.D., D.Litt., KEA-KSET., Associate Professor, Dept. CSE, School of CS&T, Faculty of Engineering Technology, G M University, Post Box No-4, PB Road, Davanagere-577006,
- 2. A Queue Data Structure is a fundamental concept in computer science used for storing and managing data in a specific order. It follows the principle of "First in, First out" (FIFO), where the first element added to the queue is the first one to be removed. It is used as a buffer in computer systems where we have speed mismatch between two devices that communicate with each other. For example, CPU and keyboard and two devices in a network Queue is also used in Operating System algorithms like CPU Scheduling and Memory Management, and many standard algorithms like Breadth First Search of Graph, Level Order Traversal of a Tree.
- 4. Queue – Linked List Implementation Linked List implementation of the queue data structure is discussed and implemented. Print ‘-1’ if the queue is empty. we maintain two pointers, front and rear. The front points to the first item of the queue and rear points to the last item. enQueue(): This operation adds a new node after the rear and moves the rear to the next node. deQueue(): This operation removes the front node and moves the front to the next node.
- 6. Follow the below steps to solve the problem: Create a class Node with data members integer data and Node* next A parameterized constructor that takes an integer x value as a parameter and sets data equal to x and next as NULL Create a class Queue with data members Node front and rear Enqueue Operation with parameter x: Initialize Node* temp with data = x If the rear is set to NULL then set the front and rear to temp and return(Base Case) Else set rear next to temp and then move rear to temp
- 7. Dequeue Operation: If the front is set to NULL return(Base Case) Initialize Node temp with front and set front to its next If the front is equal to NULL then set the rear to NULL Delete temp from the memory
- 15. Time Complexity: O(1), The time complexity of both operations enqueue() and dequeue() is O(1) as it only changes a few pointers in both operations Auxiliary Space: O(1), The auxiliary Space of both operations enqueue() and dequeue() is O(1) as constant extra space is required