Advent of Code 2025 - AP CSA Edition

Welcome to Advent of Code 2025 - AP CSA Edition

This site documents my journey through Advent of Code 2025, with all solutions written to comply with the AP Computer Science A (AP CSA) Java subset.

About This Project

Advent of Code provides excellent algorithmic challenges, but many solutions use advanced Java features beyond the AP CSA curriculum. This project demonstrates that interesting problems can be solved using only the AP subset, making these solutions valuable for:

  • AP CSA Students: See real-world applications of course concepts
  • AP CSA Teachers: Use as teaching examples and case studies
  • Self-Learners: Understand fundamental programming without advanced features

What You’ll Find Here

📝 Daily Writeups

Each day includes a detailed writeup covering:

  • Problem summary and approach
  • AP CSA Learning Objectives addressed
  • Teaching notes and pedagogical insights
  • Code explanations with compliance notes

📚 Case Studies

In-depth explorations of:

  • Algorithm optimization techniques
  • Refactoring from naive to efficient solutions
  • Teaching strategies and classroom applications
  • Alignment with CSTA Teacher Standards

✅ AP CSA Compliance

All solutions use only:

  • Primitive types (int, double, boolean)
  • String, ArrayList, and 1D arrays
  • Standard control structures (if, for, while)
  • Methods from the Java Quick Reference

Note: Occasionally, problems require exceptions (like long for large numbers). These are clearly documented with explanations.

Browse Content

By Category

By Day

Learning Objectives Coverage

This project addresses multiple AP CSA Learning Objectives (2025 CED), including:

  • LO 1.3.C: Arithmetic expressions and operators
  • LO 1.15.B: String methods and manipulation
  • LO 2.3.A: Selection statements and branching logic
  • LO 2.7.B: Iteration with while loops
  • LO 2.8.A: Iteration with for loops
  • LO 4.3.A: Working with 1D arrays
  • LO 4.9.A: Traversing ArrayList collections
  • MOD-1: Designing and implementing methods

Resources

Notes

  • Important: Solutions must be your own work. Per AoC rules, AI assistance is not allowed for solving puzzles. This project documents solutions after they’ve been completed.
  • No puzzle text or input files from the AoC website are included in this repository, in accordance with AoC guidelines.
  • This is an educational resource demonstrating AP subset compliance, not a solution key.

Happy coding and learning! 🎄✨