I would like you to check my solution.

https://www.checkio.org/mission/open-labyrinth/publications/nanpa/python-27/first/

I think my solution is not Breadth-first-search.

https://ja.wikipedia.org/wiki/%E5%B9%85%E5%84%AA%E5%85%88%E6%8E%A2%E7%B4%A2

This is Japanese Wikipedia, but in the sample, it adds the function's arg in a Queue.

I wrote this solution just following this task's hint, but it doesn't add arg in checkio().

Isn't it DFS?

Thank you.