* Added minimum waiting time problem solution using greedy algorithm
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
* ruff --fix
* Add type hints
* Added two more doc test
* Removed unnecessary comments
* updated type hints
* Updated the code as per the code review
---------
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>