24 lines
569 B
Kotlin
24 lines
569 B
Kotlin
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package moe.kageru.aoc
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fun main() {
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val input = generateSequence(::readLine)
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.map { it.toLong() }
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.toList();
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println("Part 1: ${part1(input)}")
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println("Part 2: ${part2(input)}")
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}
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fun part1(numbers: List<Long>): Long = numbers.map(::cost).sum()
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fun part2(numbers: List<Long>): Long = numbers.map { costRec(it, 0) }.sum()
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fun cost(mass: Long): Long = (mass / 3) - 2
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tailrec fun costRec(mass: Long, acc: Long): Long {
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val cost = cost(mass)
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return when {
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cost <= 0 -> acc
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else -> costRec(cost, acc + cost)
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}
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}
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