Coverage Summary for Class: Day04p1Kt (day04p1)

 package day04p1
 
 import org.apache.commons.math3.util.ArithmeticUtils
 
 fun calcTotalPoints4PileOfScratchcards(raw: String): Long =
   raw.lineSequence().sumOf { Scratchcard.from(it).points() }
 
 data class Scratchcard(val id: Int, val winningNumbers: Set<Int>, val playedNumbers: Set<Int>) {
   fun points(): Long {
     val numOfMatchedNumbers = winningNumbers.intersect(playedNumbers).size
     return if (numOfMatchedNumbers > 0) ArithmeticUtils.pow(2L, numOfMatchedNumbers - 1) else 0
   }
 
   companion object {
     private val cardRegex = """Card \s*(\d+): (.+) \| (.+)""".toRegex()
 
     fun from(raw: String): Scratchcard {
       val (id, winningNumbers, playedNumbers) = cardRegex
         .matchEntire(raw)?.destructured ?: error("no match for $raw")
 
       return Scratchcard(
         id.toInt(),
         winningNumbers.toIntSet(),
         playedNumbers.toIntSet()
       )
     }
   }
 }
 
 private val intRegex = """(\d+)""".toRegex()
 
 fun String.toIntSet(): Set<Int> =
   intRegex.findAll(this).map { it.value.toInt() }.toSet()