Description

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d8'    88           d8'   `88        `88 d8' ..8b     `88  88  
88aaaaa88a .d8888b. 88           .aaadP' 88 .P 88 .aaadP'  88  
88     88  88'  `88 88           88'     88 d' 88 88'      88  
88     88  88.  .88 Y8.   .88    88.     Y8'' .8P 88.      88  
88     88  `88888P'  Y88888P'    Y88888P  Y8888P  Y88888P d88P 
                                                               
                                                               
           dP     dP            dP   dP oo                     
 dP dP     88   .d8'            88   88                        
8888888    88aaa8P'  .d8888b. d8888P 88 dP 88d888b.            
 88 88     88   `8b. 88'  `88   88   88 88 88'  `88            
8888888    88     88 88.  .88   88   88 88 88    88            
 dP dP     dP     dP `88888P'   dP   dP dP dP    dP            
                                                               
                                                               
            88888888b                                          
 dP dP      88                                                 
8888888    a88aaaa    dP    dP 88d888b.                        
 88 88      88        88    88 88'  `88                        
8888888     88        88.  .88 88    88                        
 dP dP      dP        `88888P' dP    dP                        
                                                               

This is my approach on Advent of code 2021 with Kotlin in a functional style. For me, it is all about learning Kotlin, functional style, and having fun while doing it.

Code organization

Each puzzle of the day will have a corresponding class name Day.kt which solves that particular puzzle, for both parts 1 and 2. There is also a companion unit test which checks that the return values of a solved puzzle is the expected value.