Add Ruby sample code and How to run them

#### This issue is about Adding Ruby Sample codes and how to run.

- [ ] Issue Title is in form `Algo/DS Name [Language]`.
- [x] I searched or browsed the repo’s other issues to ensure this is not a duplicate.
- [ ] This Algo/DS is worth adding to this repository.
- [ ] Assign this issue to me (I want to work on this).
- [ ] I ensure that I am not already assigned to 2 or more issues.
- [ ] I will send my PR only after I'm assigned to this issue by any maintainer.
- [ ] I understand that I will be unassigned from this issue if I fail to send a PR for this within a week.

No files, tests, or specific algorithms are named. Start by reviewing the repository's existing samples and contribution conventions, then identify which Ruby examples and run instructions are expected; the work is done when the agreed Ruby samples and documented execution steps are added consistently.

Written by the indexing model from the issue text.