Bug Hunt Challenges

Welcome to Bug Hunt — exercises where you become the debugger.

How It Works

Each exercise contains a short Python program that looks correct but has hidden bugs. Your job:

1. Read the code and the description of what it should do.
2. Run the program and observe the output (or the crash).
3. Find every bug — each file has 3-5 intentional mistakes.
4. Fix the bugs so the program works correctly.
5. Check your work against the solution in solutions/.

Why Bug Hunting?

Reading and debugging code is a separate skill from writing it. Professional developers spend more time reading code than writing it. These exercises train your eye to spot common Python pitfalls before they bite you in your own projects.

Exercise List

File	Topic	Difficulty
01_off_by_one.py	Index errors, range(), list boundaries	Beginner
02_scope_confusion.py	Local vs global, variable shadowing	Beginner
03_mutable_defaults.py	Mutable default args, aliasing	Intermediate
04_key_and_attribute_errors.py	Dict keys, None checks, attributes	Intermediate
05_file_handling_bugs.py	File I/O, modes, encoding, paths	Intermediate
06_comparison_traps.py	is vs ==, floats, truthy/falsy	Intermediate

Tips

• Read the error messages carefully — Python tells you exactly what went wrong.
• Run the code in small pieces if a file is long.
• Add print() statements to inspect variables.
• Compare your fixes with the solutions only after you have tried on your own.