Implement the class Doubly Linked List to create a list of integers. You need to provide the implementation of the member functions as described in the following.

class DList

{

private:

Node * head;

public:

DList();

// Checks if the list is empty or not

bool emptyList();

// Inserts a new node with value ‘newV’ after the node containing value ‘oldV’. If a node with value ‘oldV’ does not exist, inserts the new node at the end.

void insert_after(int oldV, int newV);

// Deletes the node containing the specified value

void deleteNode(int value);

// Inserts a new node at the start of the list

void insert_begin(int value);

// Inserts a new node at the end of the list

void insert_end(int value);

// Displays the values stored in the list starting from head

void traverse();

// Displays the values stored in the list starting from last

};