Advent of Code Leaderboard 2023 / Day 5

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Leaderboard

	Name	Language	Tokens Sum	Tokens Part 1	Tokens Part 2	Last change
1	Valentin Slawicek	Kotlin	1036	408	628	22 months ago

Rules

You're welcome to participate alone or in a team.
You may submit multiple solutions and explore different programming languages.
Stick to the standard library of your language, no further dependencies/libraries, except the ones which OneCompiler provides (e.g. NumPy for Python).
Ensure your code aligns to the template (Python, Rust, Go, Kotlin, JavaScript, C#, TypeScript, C++, Java, C, Swift, Scala, Ruby, Bash), reading the puzzle input from stdin (terminated with end-of-file), and printing the solution to stdout.
Please refrain from making network requests, reading data from files, or storing data in variable/function/class names for reflection.
Your code must be able to process all valid Advent of Code inputs. Golfcoder might reevaluate correctness of your solution with different inputs after your submission.

408 tokens in Kotlin for part 1 by Valentin Slawicek

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dataclassMapEntry(
valsource:String,
valdestination:String,
valsourceStart:Long,
valdestinationStart:Long,
valrangeLength:Long
){
valsourceRange=LongRange(sourceStart,sourceStart+rangeLength-1)
}

funmain(){
valmapEntries=mutableListOf<MapEntry>()

varseeds:List<Long>=emptyList()

varcurrentMap=""to""// Start to end

generateSequence(::readLine)
.forEach{line->
when{
line.startsWith("seeds: ")->{
seeds=line.substringAfter("seeds: ").split(" ").map{it.toLong()}
}
line.endsWith(" map:")->{
currentMap=line.substringBefore("-")toline.substringAfter("-to-").substringBefore(" ")
}
line.isEmpty()->Unit// Skip
else->{
valmapEntryString=line.split(" ").map{it.toLong()}
mapEntries+=MapEntry(
source=currentMap.first,
destination=currentMap.second,
destinationStart=mapEntryString[0],
sourceStart=mapEntryString[1],
rangeLength=mapEntryString[2]
)
}
}
}

fungetMapEntry(source:String,number:Long):MapEntry{
// O(n), but we don't care for such small list lengths
returnmapEntries.singleOrNull{it.source==source&&it.sourceStart<=number&&it.sourceStart+it.rangeLength>number}// Mapped
?:mapEntries.first{it.source==source}.copy(sourceStart=number,destinationStart=number,rangeLength=1)// Unmapped
}

funresolve(source:String,number:Long):Long{
valmapEntry=getMapEntry(source,number)
valdestinationNumber=mapEntry.destinationStart+number-mapEntry.sourceStart
returnif(mapEntry.destination=="location"){
destinationNumber
}else{
resolve(mapEntry.destination,destinationNumber)
}
}

println(seeds.minOf{resolve("seed",it)})
}