TheDeveloperBlog.com

Home | Contact Us

C-Sharp | Java | Python | Swift | GO | WPF | Ruby | Scala | F# | JavaScript | SQL | PHP | Angular | HTML

Deletion in Doubly Linked List After The Specified Node

Deletion in Doubly Linked List After The Specified Node with Introduction, Asymptotic Analysis, Array, Pointer, Structure, Singly Linked List, Doubly Linked List, Circular Linked List, Binary Search, Linear Search, Sorting, Bucket Sort, Comb Sort, Shell Sort, Heap Sort, Merge Sort, Selection Sort, Counting Sort, Stack, Qene, Circular Quene, Graph, Tree, B Tree, B+ Tree, Avl Tree etc.

<< Back to DELETION

Deletion in doubly linked list after the specified node

In order to delete the node after the specified data, we need to perform the following steps.

  • Copy the head pointer into a temporary pointer temp.
temp = head 
  • Traverse the list until we find the desired data value.
while(temp -> data != val)
temp = temp -> next;
  • Check if this is the last node of the list. If it is so then we can't perform deletion.
if(temp -> next == NULL)
	{
return; 
	}
  • Check if the node which is to be deleted, is the last node of the list, if it so then we have to make the next pointer of this node point to null so that it can be the new last node of the list.
if(temp -> next -> next == NULL)
	{
		temp ->next = NULL;
	}
  • Otherwise, make the pointer ptr point to the node which is to be deleted. Make the next of temp point to the next of ptr. Make the previous of next node of ptr point to temp. free the ptr.
ptr = temp -> next;
		temp -> next = ptr -> next;
		ptr -> next -> prev = temp;
		free(ptr);

Algorithm

  • Step 1: IF HEAD = NULL
  •     Write UNDERFLOW
       Go to Step 9
      [END OF IF]

  • Step 2: SET TEMP = HEAD
  • Step 3: Repeat Step 4 while TEMP -> DATA != ITEM
  • Step 4: SET TEMP = TEMP -> NEXT
  •    [END OF LOOP]

  • Step 5: SET PTR = TEMP -> NEXT
  • Step 6: SET TEMP -> NEXT = PTR -> NEXT
  • Step 7: SET PTR -> NEXT -> PREV = TEMP
  • Step 8: FREE PTR
  • Step 9: EXIT

Deletion in doubly linked list after the specified node

C Function

#include<stdio.h>
#include<stdlib.h>
void create(int);
void delete_specified();
struct node
{
	int data;
	struct node *next;
	struct node *prev;
};
struct node *head;
void main ()
{
	int choice,item;
	do 
	{
		printf("1.Append List\n2.Delete node\n3.Exit\n4.Enter your choice?");
		scanf("%d",&choice);
		switch(choice)
		{
			case 1:
			printf("\nEnter the item\n");
			scanf("%d",&item);
			create(item);
			break; 
			case 2:
			delete_specified();
			break; 
			case 3:
			exit(0);
			break;	
			default:
			printf("\nPlease enter valid choice\n");
		}
				
	}while(choice != 3);
}
void create(int item)
{
   struct node *ptr = (struct node *)malloc(sizeof(struct node));
   if(ptr == NULL)
   {
       printf("\nOVERFLOW\n");
   }
   else
   {
    
    
   if(head==NULL)
   {
       ptr->next = NULL;
       ptr->prev=NULL;
       ptr->data=item;
       head=ptr;
   }
   else 
   {
       ptr->data=item;
       ptr->prev=NULL;
       ptr->next = head;
       head->prev=ptr;
       head=ptr;
   }
	printf("\nNode Inserted\n");
}
   
}
void delete_specified( )
{
	struct node *ptr, *temp; 
	int val; 
	printf("Enter the value");
	scanf("%d",&val);
	temp = head;
	while(temp -> data != val)
	temp = temp -> next;
	if(temp -> next == NULL)
	{
		printf("\nCan't delete\n");
	}
	else if(temp -> next -> next == NULL)
	{
		temp ->next = NULL;
		printf("\nNode Deleted\n");
	}
	else
	{ 
		ptr = temp -> next;
		temp -> next = ptr -> next;
		ptr -> next -> prev = temp;
		free(ptr);
		printf("\nNode Deleted\n");
	}	
}

Output

1.Append List
2.Delete node
3.Exit
4.Enter your choice?1

Enter the item
12

Node Inserted
1.Append List
2.Delete node
3.Exit
4.Enter your choice?1

Enter the item
23

Node Inserted
1.Append List
2.Delete node
3.Exit
4.Enter your choice?1

Enter the item
34

Node Inserted
1.Append List
2.Delete node
3.Exit
4.Enter your choice?2
Enter the value23

Node Deleted

Next TopicDoubly Linked List




Related Links:


Related Links

Adjectives Ado Ai Android Angular Antonyms Apache Articles Asp Autocad Automata Aws Azure Basic Binary Bitcoin Blockchain C Cassandra Change Coa Computer Control Cpp Create Creating C-Sharp Cyber Daa Data Dbms Deletion Devops Difference Discrete Es6 Ethical Examples Features Firebase Flutter Fs Git Go Hbase History Hive Hiveql How Html Idioms Insertion Installing Ios Java Joomla Js Kafka Kali Laravel Logical Machine Matlab Matrix Mongodb Mysql One Opencv Oracle Ordering Os Pandas Php Pig Pl Postgresql Powershell Prepositions Program Python React Ruby Scala Selecting Selenium Sentence Seo Sharepoint Software Spellings Spotting Spring Sql Sqlite Sqoop Svn Swift Synonyms Talend Testng Types Uml Unity Vbnet Verbal Webdriver What Wpf