EXPERIMENT 5 – Circular Linked list

Objectives:

(a). Understanding the concepts and operations of circular linked lists

(b). Implement circular linked list using dynamic structures.

Time Required: 3 hrs

Software Required:

(a). Windows OS

(b). Microsoft Visual Studio 2012/ Borland/ Dev C++

Circular Linked List

Circular Linked List is a variation of Linked list in which the first element points to the last element and the last element points to the first element. Both Singly Linked List and Doubly Linked List can be made into a circular linked list.

Singly Linked List as Circular

In singly linked list, the next pointer of the last node points to the first node.

Doubly Linked List as Circular

In doubly linked list, the next pointer of the last node points to the first node and the previous pointer of the first node points to the last node making the circular in both directions.

As per the above illustration, following are the important points to be considered.

· The last link's next points to the first link of the list in both cases of singly as well as doubly linked list.

· The first link's previous points to the last of the list in case of doubly linked list.

Basic Operations

Following are the important operations supported by a circular list.

· insert − Inserts an element at the start of the list.

· delete − Deletes an element from the start of the list.

· display − Displays the list.

Exercise:

Make a circular linked list. Insert a number in integer part and in string its property as even or odd part of node structure.

struct cnode{

int num;

string evenORodd;

…}

Insert a new node at second last position and check for the node previously at the second last position if the number it is containing is even move to the start of the circular linked list and if it’s odd shift it to the last of the circular linked list.

Even Case: