ITPEC FE Subject B October 2025 Question 6

f1 is a Rectangle(5, 2), f2 is a Cuboid(9, 4, 7) (subclass of Rectangle).

• •f1.enlarge(f2) calls Rectangle.enlarge, which adds f2.length (9) to f1.length (5) and f2.width (4) to f1.width (2)
• •Result: f1.length = 14, f1.width = 6
• •f1.output() prints (14, 6)

Why not others:
- (5, 2): ignores the enlarge call entirely
- (5, 2, 7): f1 is a Rectangle, has no height field — cannot output three values
- (9, 4): confuses f2's original dimensions with f1's result
- (9, 4, 7): outputs f2's values instead of f1's
- (14, 6, 7): incorrectly assumes f1 has a height field

Key rule: When a superclass method receives a subclass object as an argument, it only accesses fields defined in the parameter's declared type (Rectangle), not the subclass-specific fields (height).

AI-generated — may contain errors