* add typehints and docstrings
* add typehint and default value
* add typehint and default value. Removed unused variable.
* do not modifiy the given solution
* add doctests
* update sol1 after running black
* add typehint, docstring, and doctest
* update sol2 after running black
* add full problem statement and solution function with typehint and doctest
* renamed original function instead of adding new one
* don't alter original solution