2010 AP CSA FRQ 4: GridChecker - Solution

2010 AP CSA FRQ 4: GridChecker

Topic: GridWorld Case Study (Legacy)

Skills: Case study specific - Grid interface methods

Unit: Unit 4 (Data Collections) (2025-2026 AP CSA)

Points: 9 | Time: ~22 minutes

Note: This FRQ used the GridWorld/Marine Biology Case Study (no longer tested).

Part (a)

Note: This FRQ was part of the GridWorld Case Study which is no longer tested.

Try First! Attempt before viewing solution.

Solution

// GridWorld Case Study - no longer tested
// Modern equivalent: Working with Grid interfaces and 2D structures

Part (b)

The GridWorld Case Study is no longer tested on the AP exam.

Solution

// Focus on standard 2D array problems instead.

Key Concepts

✓ Interface method usage
✓ Grid traversal patterns
✓ Object retrieval from grids

Common Mistakes

✗ This question used the deprecated GridWorld Case Study
Practice Similar: 2019 FRQ 4 | 2022 FRQ 4 | 2023 FRQ 4

Official Resources

Author: Tanner Crow - AP CS Teacher, 11+ years

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