In this lab, you have to implement functions for lists:

During the class we considered the insert function within a class $($it was a method$)$

We consider the class Node with the properties int data, Node$*$ next, and Node$*$ previous

Create a recursive function that insert an element in the list given as an input, where the list is only the pointer to the head.

Possibility $1$: Node$*$ Insert$($Node$*$ head,int x$)//$ Insert the element x in the list head, and return the new list

Possibility $2$: void Insert$($Node$**$ head,int x$)//$ Insert the element x in the list head, and change the list given as an input $($pointer$)$

Possibility $3$: void Insert$($Node$*$ &head,int x$)//$ Insert the element x in the list head, and change the list given as an input $($reference$)$

We consider a an array of size n containing integers

$1.$ Create a function that returns a list l containing the unique values of a

Example: the array $[0102301]$ will return the list $(0,1,2,3)$

$2.$ Create a function that return a list l containing the occurrence of each element in a

Example: the array $[0102301]$ will return the list $(3,2,1,1)$

$3.$ Create a sorted list that returns all the elements from an array that are above a given element x

Example: the array $[481396]$ and x$=5,$ the returned list is $[689]$

$4.$ Create a Stack or a Queue class $($the choice is yours$)$ using a list instead of an array, as seen during the class

Submit only questions $1,2,3,4$ in the same file, with a main that demonstrates each function.

code in c$++$