Computer Science Exam Questions

The diagrams below show three items stored in a stack. Which sequence of operations would transform the stack from the initial state to the final state? Initial State TOP C A B Final State TOP A C B

• POP, POP, PUSH(C), PUSH(A)

• POP, POP, PUSH(A), PUSH(C)

• PUSH(A), PUSH(C), POP, POP

• POP, POP, POP, PUSH(A), PUSH(C), PUSH(B)

Which ordering below gives a working implementation for the ‘POP ( )’ operation?

• IX, V, III, I

• II, V, IV, I

• VI, IV, II, I

• IX, V, IV, I

Assume that the list is sorted. When searching the sorted list, which of the following will be found the fastest using a binary search?

• ant

• dog

• fish

• grasshopper

Figure 1 below shows the state of a stack before the POP operation is performed. Figure 2 shows the state after the POP operation is performed. Which of the following combinations of arrows correctly identifies the top of the stack structures?

• I and V

• II and VI

• III and VII

• IV and VIII

Entries in a stack are ‘ordered’. What is the meaning of this statement?

• The collection of stacks can be sorted.

• Stack entries may be compared with the ‘<’ operation.

• The entries must be stored in a linked list.

• There is a first entry, a second entry and so on.

Consider a circular queue, C, with a pointer rear that references the location of the rear of the queue. The front pointer is set to zero before any ADT operation. The following operations are performed on C. enqueue, enqueue, enqueue, dequeue, dequeue, enqueue, enqueue, enqueue, dequeue Assuming that the locations range from 0 to 4, what is the value of the pointer front?

• 0

• 1

• 2

• 3

Using the selection sort algorithm, what would the array above look like after three passes?

• 3718243230

• 3724183032

• 3718303224

• 3718243032

Which of the following statements is true?

• The bubble sort is very simple and therefore very efficient.

• The selection sort performs the same regardless of the size of the list.

• The bubble sort performs less efficient than selection sort on longer lists.

• The selection sort starts by finding the maximum element in the list and swapping it with the middle element.

Which of the diagrams below gives the state of the stack after the operations listed are performed in order?

Which of the following sequences of steps would complete the procedure?

• I – flag = true II – add 1 to count III – count = n – 1 IV – WRITE target not found

• I – flag = true II – add 1 to count III – count = n – 1 IV – WRITE target found

• I – flag = true II – add 1 to count III – count = n IV – WRITE target not found

• I – flag = true II – add 1 to count III – count = n IV – WRITE target found