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Delete node in linked list without head pointer and traversing

Problem – You have given only pointer to a particular node to delete that node without using head node and traversing

Solution – There is no practical solution possible to delete node directly by given pointer, but there is a way to delete that node logically rather than physically in memory. And the solution is to copy the data from the next node to the current node by given pointer to be deleted and delete the next node. Something like following example

Note: This solution doesn’t work if the node to be deleted is the last node of the list.

#include<iostream>
#include<stdlib.h>
using namespace std;

/* List Structure */
typedef struct Node
{
	int data;
	struct Node *link;
}node;

node *head = NULL;	// Head node to keep track of linked list

/* Driver functions */
void DeleteNode(node *node_ptr); 
void insert(int data, int position);
void print();

/* Main method */
int main()
{
	insert(0,1);	// Insert Element at first position LINKED-LIST =  / 0 /
	insert(1,2);	// Insert Element at second position LINKED-LIST = / 0 1 /
	insert(2,3);	// Insert Element at third position LINKED-LIST =  / 0 1 2 /
	insert(3,4);	// Insert Element at fourth position LINKED-LIST = / 0 1 2 3/
	insert(4,5);	// Insert Element at fourth position LINKED-LIST = / 0 1 2 3 4/
	 
	print();	// Printing Elements of Linked List
	
	DeleteNode(head);	//Deleting first node
	
	print();	// Printing Elements of Linked List
	 
	return 0;
}

/* Delete node by given pointer */
void DeleteNode(node *node_ptr)   
{
   node *next = node_ptr->link;
   node_ptr->data = next->data;
   node_ptr->link = next->link;
   
   free(next);
}

/* Function for Inserting nodes at defined position */
void insert(int data, int position)
{
	/* Declaring node */
	node *temp = (node*)malloc(sizeof(node));
	temp->data = data;
	temp->link = NULL;
	
	/* if node insertion at first point */
	if(position==1)
	{
		temp->link = head;
		head = temp;
		return ;
	}
	
	/* Adding & Adjusting node links*/
	node *traverse = head;
	for(int i=0; i<position-2; i++)
	{
		traverse = traverse->link;
	}	
	temp->link = traverse->link;
	traverse->link = temp;	
}

/* Function for Printing Linked List */
void print()
{
	printf("\n Linked List = ");
	node *p = head;
	
	while(p)
	{
		printf(" %d",p->data);
		p = p->link;
	}
	printf(" \n\n");
}

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Delete node in linked list without head pointer and traversing

Output

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