Data Structures and Algorithms

Language: Python

---

Challenges	links
array-reverse	link
array-insert-shift	link
array-binary-search	link
linked_list	link
linked_list_kth	link
linked_list_insertions	link
stacks_and_queues	link
linked_list_zip	link
stack_queue_pseudo	link
stack_queue_animal_shelter	link
stack_queue_brackets	link
trees	link
max_tree	link
tree_bsf	link
tree_fizz_buzz	link
Insertion_Sort	link

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Folder and Challenge Setup

Each type of code challenge has slightly different instructions. Please refer to the notes and examples below for instructions for each DS&A assignment type.

Data Structure: New Implementation

• Create a new folder under the python level, with the name of the data structure and complete your implementation there
  • i.e. linked_list
• Implementation (the data structure "class")
  • The implementation of the data structure should match package name
    • i.e. linked_list/linked_list.py
  • Follow Python naming conventions

    class LinkedList:
      def __init__(self):
        # ... initialization code

      def method_name(self):
        # method body
    ```

* Tests
  + Within folder `tests` create a test file called `test_[data_structure].py`
    - i.e. `tests/test_linked_list.py`
    - Your tests will then need to require the data structure you're testing
      - i.e. `from linked_list.linked_list import LinkedList`

### Data Structure: Extending an implementation

* Work within the existing data structure implementation
* Create a new method within the class that solves the code challenge
  + Remember, you'll have access to `self` within your class methods
* Tests
  + You will have folder named `tests` and within it, a test file called `test_[data_structure].py`
    - i.e. `tests/test_linked_list.py`
    - Add to the tests written for this data structure to cover your new method(s)

### Code Challenge / Algorithm

Code challenges should be completed within a folder named `code_challenges` under the `python` level

* Daily Setup:
  + Create a new folder under the `python` level, with the name of the code challenge
    - Each code challenge assignment identifies the branch name to use, for example 'find-maximum-value'
    - For clarity, create your folder with the same name, ensuring that it's `snake_cased`
    - i.e. For a challenge named 'find_maximum_value', create the folder:`code_challenges/find_maximum_value`
  + Code Challenge Implementation
    - Each code challenge requires a function be written, for example "find maximum value"
    - Name the actual challenge file with the name of the challenge, in `snake_case`
      - i.e. `find_maximum_value.py`
    - Reminder: Your challenge file will then need to require the data structure you're using to implement
      - i.e. `from linked_list.linked_list import LinkedList`
    - Your challenge function name is up to you, but name something sensible that communicates the function's purpose. Obvious is better than clever
      - i.e. `find_maximum_value(linked_list)`
  + Tests
    - Ensure there is a `tests` folder at the root of project.
      - i.e. a sibling of this document.
    - within it, a test file called `test_[challenge].py`
      - i.e. `tests/find_maximum_value.py`
      - Your test file would require the challenge file found in the directory above, which has your exported function
        - i.e. `from code_challenges.find_maximum_value import find_maximum_value`

## Running Tests

If you setup your folders according to the above guidelines, running tests becomes a matter of deciding which tests you want to execute.  Jest does a good job at finding the test files that match what you specify in the test command

From the root of the `data-structures-and-algorithms/python` folder, execute the following commands:

* **Run every possible test** - `pytest`
* **Run filtered tests** - `pytest -k some_filter_text`
* **Run in watch mode** - `ptw` or `pytest-watch`..