Answer to Question #264550 in C++ for Bsnsbjsn

Question

Write a program in c++ and implement all basic operation (create new node, search element in list, delete from list etc) in doubly linked list

Answer 1

#include <bits/stdc++.h>
using namespace std;


class Node
{
	public:
	int data;
	Node* next;
	Node* prev;
};


void push(Node** hd_ref, int new_d)
{
	Node* n = new Node();
	n->data = new_d;


	n->next = (*hd_ref);
	n->prev = NULL;
	if ((*hd_ref) != NULL)
		(*hd_ref)->prev = n;
	(*hd_ref) = n;
}


void insertAfter(Node* pv_node, int n_data)
{
	if (pv_node == NULL)
	{
		cout<<"Cannot be NULL";
		return;
	}


	Node* n = new Node();
	n->data = n_data;
	n->next = pv_node->next;
	pv_node->next = n;
	n->prev = pv_node;
	if (n->next != NULL)
		n->next->prev = n;
}
void append(Node** hd_ref, int new_d)
{
	Node* n = new Node();


	Node* ls = *hd_ref; 
	n->data = new_d;


	n->next = NULL;


	if (*hd_ref == NULL)
	{
		n->prev = NULL;
		*hd_ref = n;
		return;
	}


	while (ls->next != NULL)
		ls = ls->next;


    	ls->next = n;
    
    	n->prev = ls;


	return;
}
void display(Node* nd)
{
	Node* lt;
	cout<<"\nForward direction \n";
	while (nd != NULL)
	{
		cout<<" "<<nd->data<<" ";
		lt = nd;
		nd = nd->next;
	}


	cout<<"\nReverse direction \n";
	while (lt != NULL)
	{
		cout<<" "<<lt->data<<" ";
		lt = lt->prev;
	}
}
int main()
{
	Node* hd = NULL;
	append(&hd, 1);
	push(&hd, 2);
	push(&hd, 3);
	append(&hd, 4);
	insertAfter(hd->next, 5);


	cout << "DLL: ";
	display(hd);


	return 0;
}