write explanation to solution of wormhole sort

[Streakwind]

Place an "x" in the corresponding checkbox if it is done or does not apply to this pull request.

• I have tested my code.
• I have added my solution according to the steps here.
• I have followed the code conventions mentioned here.
  • I understand that if it is clear that I have not attempted to follow these conventions, my PR will be closed.
  • If changes are requested, I will re-request a review after addressing them.
• I have linked this PR to any issues that it closes.

The explanation only covers the first solution, which uses Binary Search and Floodfill.

[Streakwind]

There's one segment that is duplicated. I will fix this when I get access to my computer.

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. Please address the requested changes and re-request reviews. Thank you for your contribution!

[Streakwind]

Is it possible for someone to remove the stale label? I have requested a review a week ago.