Practice · 2 of 3

Abstract shapes with conditional overrides

CHALLENGE

Difficulty: advanced+25 XP

Implement Shape (abstract): public abstract int area(); plus a concrete describe() returning "shape:" + area(). Subclass Square (side; area = side*side) and Rect (w, h; area = w*h). Then implement totalArea(ArrayList<Shape>). The list may contain both; use the abstract reference type.

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