Exercises — Stage 3: Add the Scoreboard

Exercise 1: View history in different formats

Goal: Get comfortable flipping between log views.

Steps:

1. Run git log.
2. Run git log --oneline.
3. Run git log --oneline --graph.
4. Run git log --stat.

What happened: Each flag gives you a different angle on the same three commits. --oneline is compact, --graph draws a line between commits, --stat adds a summary of which files changed in each commit.

Exercise 2: Inspect one commit

Goal: See exactly what changed in a single save point.

Steps:

1. Run git log --oneline and copy the short hash of the Stage 2 commit.
2. Run git show <hash>.

What happened: git show prints the commit message and the full diff of what that commit changed. This is how you audit old changes.

Exercise 3: Change the starting lives

Goal: Practice the edit-commit loop.

Steps:

1. Change <p>Lives: 3</p> to <p>Lives: 5</p>.
2. Reload the browser to see 5 lives.
3. Run git diff to review your change.
4. Revert with git restore index.html (no commit needed).
5. Reload the browser — back to 3 lives.

What happened: git restore <file> throws away unsaved changes and brings the file back to the last committed version. Editing is risk-free when Git has your back.

Exercise 4: Count your commits

Goal: Learn how to count history programmatically.

Steps:

1. Run git rev-list --count HEAD.

What happened: rev-list --count HEAD prints the number of commits reachable from the current position. You should see 3. This is handy in scripts and CI systems.