Programming 1

This repository contains simple C programs and lesson notes for an introductory Programming 1 course. The code files demonstrate basic C concepts (data types, arithmetic, input/output, conditionals, operators, and memory access).

Repository structure

• Lesson1/
  • lesson1.c — simple arithmetic and printf examples.
  • in-class-work1.c — reads two integers and prints sum, subtraction, division, multiplication and modulus results.
  • lesson1.md — lesson notes about basic data types and short examples.
• Lesson2/
  • lesson2.c — examples demonstrating averages, even/odd check, if/else if chains and scanf usage.
  • lesson2.md — lesson notes about the & operator, memory concepts and conditional statements.
  • lesson2.exe — compiled binary (checked in). You can remove this if you prefer source-only repositories.

Goals / contract

• Inputs: C source files in Lesson1/ and Lesson2/.
• Output: buildable executables and console output demonstrating the examples.
• Success: Each .c file compiles and runs on a machine with a C compiler (GCC/MinGW/MSYS) and produces the expected console output.

Edge cases to watch

• Missing or invalid user input to scanf (programs don't currently validate input return values).
• Integer division yields truncated results; expect that in examples using /.

Prerequisites

• A C compiler such as gcc available in your PATH, or use the provided VS Code build task which uses MSYS2's gcc.exe.
• Windows PowerShell (examples below use PowerShell). Adjust commands for other shells.

Build and run (PowerShell)

Recommended: use the VS Code build task C/C++: gcc.exe build active file (already present in the workspace tasks).

From PowerShell you can compile and run each lesson manually. Run these commands from the repository root (where this readme.md lives):

# Compile Lesson1 examples
gcc -g .\Lesson1\lesson1.c -o .\Lesson1\lesson1.exe
gcc -g .\Lesson1\in-class-work1.c -o .\Lesson1\in-class-work1.exe

# Run
.\Lesson1\lesson1.exe
.\Lesson1\in-class-work1.exe

# Compile and run Lesson2
gcc -g .\Lesson2\lesson2.c -o .\Lesson2\lesson2.exe
.\Lesson2\lesson2.exe

If gcc is not on your PATH but you have MSYS2 installed like the VS Code task, you can run the same commands with the full gcc.exe path used by the task.

What each source file demonstrates (quick)

• Lesson1/lesson1.c

  • Declares integer variables, computes sum and multiply, and prints results with printf.

• Lesson1/in-class-work1.c

  • Prompts for two integers via scanf and prints the five basic arithmetic operations (sum, subtract, divide, multiply, mod).
  • Note: divide is integer division; decimals are truncated.

• Lesson2/lesson2.c

  • Calculates an average of five integers.
  • Demonstrates an even/odd check using %.
  • Contains an interactive scanf example that reads a grade and prints a letter grade using an if / else if ladder.

Common pitfalls and recommendations

• Always check the return value of scanf in real programs to avoid undefined behaviour when input is missing or malformed.
• For floating-point division, use float/double variables and %f / %lf in printf/scanf.
• Remove compiled binaries (*.exe) from source control or add them to .gitignore to keep the repo source-only.

Next steps (suggested)

• Add small unit-test-like input scripts or expected-output comments for each example.
• Add input validation to scanf calls.
• Add a .gitignore to exclude binaries and object files.

Contributing

Open a pull request with small, focused changes. If you add exercises, include example inputs and expected outputs.

License

Place a license file if you want to share these materials publicly (e.g., LICENSE with CC-BY or MIT as appropriate).

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Generated: documented code examples and build instructions for this workspace.