Edward Nuno 94f38dd88c
[mypy] Fix type annotations for linked_stack.py (#5576)
* Fix type annotations for linked_stack.py

* Replace Optional with inline union type

* Rename linked_stack to stack_with_singly_linked_list

* Rename stack_using_dll to stack_with_doubly_linked_list

* updating DIRECTORY.md

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2021-10-31 17:03:03 +01:00
..
2020-11-02 00:35:31 +08:00