Singly-linked list: A simple list is implemented with node structure:

struct node { int data; node *next; node(); }; node *L;

If L is a pointer to the first item on a list,then the following is a recursive function for printing the list in reverse order:

void rev(node *L) {

if (L == NULL) return;

rev(L->next);

cout << L->data;

return;

}

Modify this function to write another recursive function (you must use recursion, such as the one above):

node *copy(node *L) {

to create a new duplicate copy of the original list and return a pointer to the new list.