Take this Quiz: A-Level Computer Science: Programming and Paradigms | Zestly

Question 1

Consider this pseudocode: total = 0. FOR i FROM 1 TO 4: total = total + i. total = total + 1. END FOR. PRINT total. What is the final value printed?

Accepted Answer

14

Answer

11

Answer

15

Answer

10

Question 2

Consider the recursive function: FUNCTION calc(n): IF n < 2 THEN RETURN 1. ELSE RETURN n + calc(n - 1). END IF. END FUNCTION. What is the result of calling calc(3)?

Accepted Answer

6

Answer

5

Answer

3

Answer

4

Question 3

Consider this pseudocode: count = 5. PROCEDURE tally(): DECLARE count AS LOCAL. count = 20. PRINT count. END PROCEDURE. CALL tally(). PRINT count. What two values are printed, in that order?

Accepted Answer

Twenty and then five: the declaration inside the procedure creates a second variable that merely happens to share the name, so the assignment lands on that one, and the outer variable is untouched once the procedure ends.

Answer

Twenty and then twenty, since assigning to a name changes whichever variable carries that name.

Answer

Five and then five, since a procedure cannot print a value different from the one held outside it.

Answer

Five and then twenty, because the outer variable is updated only after the procedure has finished.

Question 4

A BankAccount class keeps its balance in a field that no code outside the class can reach, and offers deposit and withdraw methods that check the amount before changing it. A SavingsAccount extends BankAccount and supplies its own version of withdraw, which refuses more than three withdrawals in a month. Which idea is at work in each of those two things, in that order?

Answer

Inheritance for the hidden balance, and encapsulation for the subclass's own version of withdraw.

Answer

Polymorphism for the hidden balance, and abstraction for the subclass's own version of withdraw.

Answer

Abstraction for the hidden balance, and inheritance for the subclass's own version of withdraw.

Answer

Encapsulation for the hidden balance reached only through methods, and polymorphism for the subclass supplying its own version of a method its parent already has.

Question 5

Two classes, Printer and Scanner, both need a method to log activity. If you force a 'Printer inherits from Scanner' relationship, what is the primary design flaw?

Answer

It forces the use of composition

Answer

It violates encapsulation

Answer

It creates an illogical 'is-a' relationship

Answer

It prevents polymorphism