CS 61C Quiz - Week 2-1-1: Monday

Question 1:

1.  Which of the following statements are true about a successful call
to malloc, that is, a call that returns a non-NULL pointer?
None may be true, or more than one statement may be true.
Briefly explain your answer.


a.  A successful call to malloc will always reduce the
number of free blocks.


b.  A successful call to malloc may leave the number of free blocks
unchanged.


c.  A successful call to malloc may increase the number
of free blocks.

Question 2:

2.  Which of the following statements are true about a call to free?
None may be true, or more than one statement may be true.
Briefly explain your
answer.


a.  A call to free always increases the number of free blocks.


b.  A call to free may leave the number of free blocks unchanged.


c.  A call to free may reduce the number of free blocks by 1,
but never by more than 1.


d.  A call to free may reduce the number of free blocks by 2 or more.

Question 3:

3.  What is the Java equivalent to malloc in C? What is the Java
equivalent to free in C? Why can't someone build an automatic memory
allocation / deallocation system for C like those available for
Java?

Question 4:

Consider a structure of the form
 ___________      ___________
|   |   |   |    |  /|   |   |
| o |   | o----->| / |   | o |
|_|_|___|___|    |/__|___|_|_|
  |                        |
 _v_________      _________v_
|  /|   |   |    |  /|   |  /|
| / |   | o----->| / |   | / |
|/__|___|___|    |/__|___|/__|

Can this structure be reclaimed using the reference count method?
Can it be reclaimed using the mark and sweep method?
Briefly explain your answers.

Question 5:

5. What did you find difficult or confusing about the reading? If
  nothing was difficult or confusing, tell us what you found most
  interesting. Please be as specific as possible.

Send a confirmation email to my class account.