Multiple Choice

Multiple Choice Sections 5.1-5.2 Linked List Fundamentals

1. Suppose cursor points to a node in a linked list (using the node definition with member functions called data and link). What statement changes cursor so that it points to the next node?
   • A. cursor++;
   • B. cursor = link( );
   • C. cursor += link( );
   • D. cursor = cursor->link( );

2. Suppose cursor points to a node in a linked list (using the node definition with member functions called data and link). What Boolean expression will be true when cursor points to the tail node of the list?
   • A. (cursor == NULL)
   • B. (cursor->link( ) == NULL)
   • C. (cursor->data( ) == NULL)
   • D. (cursor->data( ) == 0.0)
   • E. None of the above.

3. Why does our node class have two versions of the link member function?
   • A. One is public, the other is private.
   • B. One is to use with a const pointer, the other with a regular pointer.
   • C. One returns the forward link, the other returns the backward link.
   • D. One returns the data, the other returns a pointer to the next node.

4. Suppose that p is a pointer variable that contains the NULL pointer. What happens if your program tries to read or write *p?
   • A. A syntax error always occurs at compilation time.
   • B. A run-time error always occurs when *p is evaluated.
   • C. A run-time error always occurs when the program finishes.
   • D. The results are unpredictable.

5. Suppose that f is a function with a prototype like this:

    void f(________ head_ptr); // Precondition: head_ptr is a head pointer for a linked list. // Postcondition: The function f has done some computation with // the linked list, but the list itself is unchanged. 

   What is the best data type for head_ptr in this function?
   • A. node
   • B. const node
   • C. node*
   • D. const node*

6. Suppose that f is a function with a prototype like this:

    void f(________ head_ptr); // Precondition: head_ptr is a head pointer for a linked list. // Postcondition: The function f has done some manipulation of // the linked list, and the list might now have a new head node. 

   What is the best data type for head_ptr in this function?
   • A. node
   • B. node&
   • C. node*
   • D. node*&

   Multiple Choice Section 5.3 The Bag ADT with with a Linked List

7. In the linked list version of the bag class a member variable many_nodes is used to keep track of how long the linked list is. Why not just make a call to the list toolkit function list_length()?
   • A. The list_length() function is O(n) and the alternative is O(1).
   • B. The list_length() function is private.
   • C. The list_length() function results in an infinite loop for circular lists.
   • D. The list_length() function works only for lists of integers.

8. Suppose that the bag is implemented with a linked list. Which of these operations are likely to have a constant worst-case time?
   • A. insert
   • B. count
   • C. erase_one
   • D. None of (A), (B), and (C) have a constant worst-case time
   • E. TWO of (A), (B), and (C) have a constant worst-case time
   • F. ALL of (A), (B), and (C) have a constant worst-case time