Here are the instructions you can copy and paste into both the README.md file in the repository and the email you send to the class.

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Source Code Management Exercise

Objective

In this exercise, you will demonstrate your understanding of Git and GitHub by forking this repository, adding a Python function, and submitting a pull request. You will write a function to calculate the Greatest Common Divisor (GCD) of two integers using the Euclidean algorithm and follow a precise workflow to manage your source code.

Instructions

Step 1: Fork the Repository

• Fork this repository to your own GitHub account by clicking the Fork button in the upper right corner.

Step 2: Clone Your Fork

• Clone the forked repository to your local machine. Open your terminal and run the following command:

  git clone https://github.com/<your-github-username>/source-code-management-exercise.git

Step 3: Create a New Branch

• Create a new branch to work on your feature. Run the following commands:

  cd source-code-management-exercise
  git checkout -b gcd-feature

Step 4: Create Your Submission File

• Inside the students_submissions/ directory, create a new Python file named gcd_<GitHubUsername>.py. Replace <GitHubUsername> with your actual GitHub username.
  • Example: If your GitHub username is johndoe, name your file gcd_johndoe.py.

Step 5: Implement the gcd Function

• In your gcd_<GitHubUsername>.py file, implement the following function:

  def gcd(a: int, b: int) -> int:
      """
      Calculate the greatest common divisor (GCD) of two integers a and b
      using the Euclidean algorithm.
      """
      # Implement your solution here
      pass

• Test your function with some basic test cases inside your file. You can use print statements to verify your implementation.

Example:

def gcd(a: int, b: int) -> int:
    while b:
        a, b = b, a % b
    return a

# Test cases
print(gcd(54, 24))  # Expected output: 6
print(gcd(48, 18))  # Expected output: 6
print(gcd(101, 10))  # Expected output: 1

Step 6: Commit Your Changes

• Once your function is implemented, stage and commit your changes:

  git add students_submissions/gcd_<GitHubUsername>.py
  git commit -m "Implemented GCD function"

Step 7: Push the Branch to GitHub

• Push your changes to the gcd-feature branch in your forked repository:

  git push origin gcd-feature

Step 8: Create a Pull Request

• Go to your forked repository on GitHub and click the Compare & pull request button.
• Make sure to select your gcd-feature branch as the source and the original repository’s main branch as the destination.
• Submit the pull request.

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Naming Conventions

To ensure your submission is automatically checked, you must follow these naming conventions:

1. Your Python file must be placed in the students_submissions/ directory.
2. The file must be named gcd_<GitHubUsername>.py, where <GitHubUsername> is your actual GitHub username (e.g., gcd_johndoe.py).
3. Your file must contain a function named gcd(a: int, b: int) -> int.

If you do not follow these conventions, your submission will not be automatically tested, and you may be asked to resubmit.

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Submission Deadline

• Your pull request must be submitted by [INSERT DEADLINE DATE AND TIME].

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Notes:

• If you encounter any issues, feel free to reach out for help.
• Remember to test your function with a variety of inputs to ensure it works correctly.
• Follow the naming conventions carefully to avoid any issues with the automatic testing.

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