README.md

Control Flow (Python)

This module practices branching, looping, and sentinel-driven iteration.

Learning Metadata

• Difficulty: Beginner.
• Estimated Time: 20-35 minutes.
• Prerequisites: 01-foundations/types-and-io, 01-foundations/operators-and-expressions.
• Cross-Language Lens: Compare braces-and-loops in C++, C#, and Go with Python indentation while keeping the underlying branching logic identical.

Quick Run

python example/main.py

Topics Covered

• Conditional branches for FizzBuzz-style rules.
• For loops with clear termination conditions.
• While/for sentinel loops using stop value -1.
• Handling empty input sequences safely.

Common Pitfalls

• Not handling non-positive upper bounds before entering loops.
• Forgetting to stop on sentinel values in streaming input.
• Dividing by zero when no values were collected.

Exercise Focus

• exercises/01.py: run FizzBuzz rules from 1 to N using condition priority.
• exercises/02.py: read integers until -1 and print average when values exist.

Exercise Specs

1. exercises/01.py

• Input: positive integer N.
• Output: sequence with Fizz, Buzz, or FizzBuzz substitutions.
• Edge cases: N <= 0; multiples of both 3 and 5.

2. exercises/02.py

• Input: integer stream terminated by -1.
• Output: average of entered values or a no-data message.
• Edge cases: first value already -1; negative values other than sentinel.

Checkpoint

• I can explain the core ideas of this module.
• I can run and modify example/main.py.
• I completed exercises/01.py.
• I completed exercises/02.py.
• I validated at least one edge case for each exercise.