Circular linked list insertion at specific position
In single linked list, every node points to its next node in the sequence and the last node points NULL. But in circular linked list, every node points to its next node in the sequence but the last node points to the first node in the list. A circular linked list is a sequence of elements in which every element has a link to its next element in the sequence and the last element has a link to the first element. That means circular linked list is similar to the single linked list except that the last node points to the first node in the list In a circular linked list, we perform the following operations... Before we implement actual operations, first we need to setup empty list. First perform the following steps before implementing actual operations.
In a circular linked list, the insertion operation can be performed in three ways. They are as follows...
We can use the following steps to insert a new node at beginning of the circular linked list...
We can use the following steps to insert a new node at end of the circular linked list...
We can use the following steps to insert a new node after a node in the circular linked list...
In a circular linked list, the deletion operation can be performed in three ways those are as follows...
We can use the following steps to delete a node from beginning of the circular linked list...
We can use the following steps to delete a node from end of the circular linked list...
We can use the following steps to delete a specific node from the circular linked list...
We can use the following steps to display the elements of a circular linked list...
#include
#include
void insertAtBeginning(int);
void insertAtEnd(int);
void insertAtAfter(int,int);
void deleteBeginning();
void deleteEnd();
void deleteSpecific(int);
void display();
struct Node
{
int data;
struct Node *next;
}*head = NULL;
void main()
{
int choice1, choice2, value, location;
clrscr();
while(1)
{
printf("\n*********** MENU *************\n");
printf("1. Insert\n2. Delete\n3. Display\n4. Exit\nEnter your choice: ");
scanf("%d",&choice1);
switch()
{
case 1: printf("Enter the value to be inserted: ");
scanf("%d",&value);
while(1)
{
printf("\nSelect from the following Inserting options\n");
printf("1. At Beginning\n2. At End\n3. After a Node\n4. Cancel\nEnter your choice: ");
scanf("%d",&choice2);
switch(choice2)
{
case 1: insertAtBeginning(value);
break;
case 2: insertAtEnd(value);
break;
case 3: printf("Enter the location after which you want to insert: ");
scanf("%d",&location);
insertAfter(value,location);
break;
case 4: goto EndSwitch;
default: printf("\nPlease select correct Inserting option!!!\n");
}
}
case 2: while(1)
{
printf("\nSelect from the following Deleting options\n");
printf("1. At Beginning\n2. At End\n3. Specific Node\n4. Cancel\nEnter your choice: ");
scanf("%d",&choice2);
switch(choice2)
{
case 1: deleteBeginning();
break;
case 2: deleteEnd();
break;
case 3: printf("Enter the Node value to be deleted: ");
scanf("%d",&location);
deleteSpecic(location);
break;
case 4: goto EndSwitch;
default: printf("\nPlease select correct Deleting option!!!\n");
}
}
EndSwitch: break;
case 3: display();
break;
case 4: exit(0);
default: printf("\nPlease select correct option!!!");
}
}
}
void insertAtBeginning(int value)
{
struct Node *newNode;
newNode = (struct Node*)malloc(sizeof(struct Node));
newNode -> data = value;
if(head == NULL)
{
head = newNode;
newNode -> next = head;
}
else
{
struct Node *temp = head;
while(temp -> next != head)
temp = temp -> next;
newNode -> next = head;
head = newNode;
temp -> next = head;
}
printf("\nInsertion success!!!");
}
void insertAtEnd(int value)
{
struct Node *newNode;
newNode = (struct Node*)malloc(sizeof(struct Node));
newNode -> data = value;
if(head == NULL)
{
head = newNode;
newNode -> next = head;
}
else
{
struct Node *temp = head;
while(temp -> next != head)
temp = temp -> next;
temp -> next = newNode;
newNode -> next = head;
}
printf("\nInsertion success!!!");
}
void insertAfter(int value, int location)
{
struct Node *newNode;
newNode = (struct Node*)malloc(sizeof(struct Node));
newNode -> data = value;
if(head == NULL)
{
head = newNode;
newNode -> next = head;
}
else
{
struct Node *temp = head;
while(temp -> data != location)
{
if(temp -> next == head)
{
printf("Given node is not found in the list!!!");
goto EndFunction;
}
else
{
temp = temp -> next;
}
}
newNode -> next = temp -> next;
temp -> next = newNode;
printf("\nInsertion success!!!");
}
EndFunction:
}
void deleteBeginning()
{
if(head == NULL)
printf("List is Empty!!! Deletion not possible!!!");
else
{
struct Node *temp = head;
if(temp -> next == head)
{
head = NULL;
free(temp);
}
else{
head = head -> next;
free(temp);
}
printf("\nDeletion success!!!");
}
}
void deleteEnd()
{
if(head == NULL)
printf("List is Empty!!! Deletion not possible!!!");
else
{
struct Node *temp1 = head, temp2;
if(temp1 -> next == head)
{
head = NULL;
free(temp1);
}
else{
while(temp1 -> next != head){
temp2 = temp1;
temp1 = temp1 -> next;
}
temp2 -> next = head;
free(temp1);
}
printf("\nDeletion success!!!");
}
}
void deleteSpecific(int delValue)
{
if(head == NULL)
printf("List is Empty!!! Deletion not possible!!!");
else
{
struct Node *temp1 = head, temp2;
while(temp1 -> data != delValue)
{
if(temp1 -> next == head)
{
printf("\nGiven node is not found in the list!!!");
goto FuctionEnd;
}
else
{
temp2 = temp1;
temp1 = temp1 -> next;
}
}
if(temp1 -> next == head){
head = NULL;
free(temp1);
}
else{
if(temp1 == head)
{
temp2 = head;
while(temp2 -> next != head)
temp2 = temp2 -> next;
head = head -> next;
temp2 -> next = head;
free(temp1);
}
else
{
if(temp1 -> next == head)
{
temp2 -> next = head;
}
else
{
temp2 -> next = temp1 -> next;
}
free(temp1);
}
}
printf("\nDeletion success!!!");
}
FuctionEnd:
}
void display()
{
if(head == NULL)
printf("\nList is Empty!!!");
else
{
struct Node *temp = head;
printf("\nList elements are: \n");
while(temp -> next != head)
{
printf("%d ---> ",temp -> data);
}
printf("%d ---> %d", temp -> data, head -> data);
}
}
Output |