CSC 212 Ch 8 Multiple Choice

If the characters 'D', 'C', 'B', 'A' are placed in a queue (in that order), and then removed one at a time, in what order will they be removed?

DCBA

I have implemented the queue with a circular array, keeping track of first, last, and count (the number of items in the array). Suppose first is zero, and last is CAPACITY-1. What can you tell me about count?

count could be zero or CAPACITY, but no other values could occur.

If data is a circular array of CAPACITY elements, and last is an index into that array, what is the formula for the index after last?

(last + 1) % CAPACITY

In the linked list implementation of the queue class, where does the push member function place the new entry on the linked list?

At the tail

I have implemented the queue with a linked list, keeping track of a front pointer and a rear pointer. Which of these pointers will change during an insertion into an EMPTY queue?

Both change (the rear_ptr and the front_ptr)

In the circular array version of the queue class (with a fixed-sized array), which operations require linear time for their worst-case behavior?

None of these operations require linear time. (front, push, empty)

In the linked-list version of the queue class, which operations require linear time for their worst-case behavior?

None of these operations require linear time. (front, push, empty)

I have implemented the queue with a linked list, keeping track of a front pointer and a rear pointer. Which of these pointers will change during an insertion into a NONEMPTY queue?

Only rear_ptr changes.

One difference between a queue and a stack is:

Queues use two ends of the structure; stacks use only one.

Consider the implementation of the queue using a circular array. What goes wrong if we try to keep all the items at the front of a partially-filled array (so that data[0] is always the front).

The get_front function would require linear time.

Suppose top is called on a priority queue that has exactly two entries with equal priority. How is the return value of top selected?

This can never happen (violates the precondition)

Suppose we have a circular array implementation of the queue class, with ten items in the queue stored at data[2] through data[11]. The CAPACITY is 42. Where does the push member function place the new entry in the array?

data[12]

Which of the following expressions evaluates to true with approximate probability equal to P? (P is double and 0 <= P <= 1).

rand() < P