|                         _...._
                         \  _  /                    .::o:::::.
                          (\o/)                    .:::'''':o:.
                      ---  / \  ---                :o:_    _:::
                           >*<                     `:}_>()<_{:'
                          >0<@<                 @    `'//\\'`    @
                         >>>@<<*              @ #     //  \\     # @
                        >@>*<0<<<           __#_#____/'____'\____#_#__
                       >*>>@<<<@<<         [__________________________]
                      >@>>0<<<*<<@<         |=_- .-/\ /\ /\ /\--. =_-|
                     >*>>0<<@<<<@<<<        |-_= | \ \\ \\ \\ \ |-_=-|
                    >@>>*<<@<>*<<0<*<       |_=-=| / // // // / |_=-_|
      \*/          >0>>*<<@<>0><<*<@<<      |=_- |`-'`-'`-'`-'  |=_=-|
  ___\\U//___     >*>>@><0<<*>>@><*<0<<     | =_-| o          o |_==_|
  |\\ | | \\|    >@>>0<*<<0>>@<<0<<<*<@<    |=_- | !     (    ! |=-_=|
  | \\| | _(UU)_ >((*))_>0><*<0><@<<<0<*<  _|-,-=| !    ).    ! |-_-=|_
  |\ \| || / //||.*.*.*.|>>@<<*<<@>><0<<@>>>>>|  ( ~~~ )/   (((((((())))))))
      ~~~~~~~~         '""""`------'  `w---w`     `------------'

In this repository, I'm about to provide solutions for the Advent of Code¹ puzzles using Kotlin language.

I decided to do the Advent of Code in Kotlin, as it is my favorite programming language which I use way too infrequently. I'm only able to use them in my side projects and unfortunately not in my professional career at my current employer.
I use this event to get a broader knowledge about the Kotlin standard library.

For each day/puzzle there is a separate file inside the source folder with the pattern DayXX (e.g. Day01). This file contains all the code that was used to solve the puzzle.
The correctness is checked using a JUnit 5 tests. There is one test file for each day using the name pattern DayXXTest (e.g. Day01Test). These tests use the sample input from the puzzle explanation to check if the code is correct. Thereafter, the code is called with the real puzzle input.
This input data is stored in text files in the "input" folder on the project root. The file name pattern of the input files is dayXX.txt (e.g. day01.txt). The mentioned sample data is stored in files with the name pattern dayXX_example.txt ( e.g. day01_example.txt).

The described files described in the section "Repo Structure" can be generated for a specific day using the command make new_day. This will generate the files required for the current day of the month and the current year. This behavior can be overridden using make new_day DAY=<day> YEAR=<year> (e.g. make new_day DAY=1 YEAR=2019).

To download the actual puzzle input when executing the make new_day ... command (only possible when the puzzle for the requested day was already released) and be able to automatically upload your puzzle answers, you need to store your session cookie to the file session.txt in the project root. The file content should look like session=abc...xyz.

I tried to log my results and thoughts for each puzzle after solving it.

I tried to log my results and thoughts for each puzzle after solving it.