Consider the Node structure as following

$/*$ Node of a doubly linked list $*/$

struct Node $\{$

int data;

Node $*$next; $//$ Pointer to next node in DLL

Node $*$prev; $//$ Pointer to previous node in DLL

$\}$;

What will be the code for missing step in C$++?//$ may need two lines of code

$/*$ Given a reference $($pointer to pointer$)$ to the head of a list and an int, inserts a new node on the front of the list. $*/$

void push$($Node$**$ head$\_$ref, int new$\_$data$)\{$

$/*1.$ allocate new node $*/$

$/*2.$ put in the data into new node $*/$

$/*3.$ Make next of new node as head and previous as NULL $*/$

$/*4.$ change prev of head node to new node $*/$

$/*5.\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_*/$

$\}$