aoc-old/aoc/src/main/scala/aoc/y2019/Day02.scala

40 lines
1.0 KiB
Scala

package aoc.y2019
import aoc.Day
import cats.data.State
object Day02 extends Day {
import Day05.Machine, Day05.MachineState, Day05.executeMachine
def initialReplacement(noun: Int, verb: Int): MachineState = State { m =>
(m.copy(m.memory.updated(1, noun).updated(2, verb)), false)
}
def runMachine(memory: Vector[Int], noun: Int, verb: Int): Int = {
val initialState = Machine(memory)
val runMachine = for {
_ <- initialReplacement(noun, verb)
run <- executeMachine
} yield run
val endState = runMachine.runS(initialState).value
endState.memory(0)
}
override def part1(input: String): String = {
val memory = input.split(",").map(_.toInt).toVector
runMachine(memory, 12, 2).toString
}
override def part2(input: String): String = {
val memory = input.split(",").map(_.toInt).toVector
val magic = 19690720
val solutions = for {
noun <- 0 to 99
verb <- 0 to 99 if runMachine(memory, noun, verb) == magic
} yield noun * 100 + verb
solutions.head.toString
}
}