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eugene70/Aoc2020_Day12.scala

Created February 26, 2021 13:02
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Aoc2020_Day12.scala
package aoc2020
object Day12:
import Direction._
import Action._
enum Direction:
case North, East, West, South
def face(op: Action, amt: Int): Direction = op match
case TurnLeft => roundRight(roundRight.lastIndexOf(this) - amt / 90)
case TurnRight => roundRight(roundRight.indexOf(this) + amt / 90)
case _ => this
enum Action:
case GoForward, GoNorth, GoEast, GoWest, GoSouth, TurnLeft, TurnRight
def move(ship: Ship, amt: Int): Ship =
val newDir = ship.dir.face(this, amt)
val newPos = this match
case GoNorth => Position(ship.pos.x, ship.pos.y + amt)
case GoEast => Position(ship.pos.x + amt, ship.pos.y)
case GoSouth => Position(ship.pos.x, ship.pos.y - amt)
case GoWest => Position(ship.pos.x - amt, ship.pos.y)
case GoForward => forward(newDir, ship.pos, amt)
case _ => ship.pos
Ship(newDir, newPos)
def move2(ship: Ship, amt: Int): Ship =
val newDir = ship.dir.face(this, amt)
val newPos = this match
case GoForward => forward2(ship, amt)
case _ => ship.pos
val newWaypoint = (this, amt) match
case (GoForward, _) => ship.waypoint
case (GoNorth, n) => Position(ship.waypoint.x, ship.waypoint.y + n)
case (GoEast, n) => Position(ship.waypoint.x + n, ship.waypoint.y)
case (GoSouth, n) => Position(ship.waypoint.x, ship.waypoint.y - n)
case (GoWest, n) => Position(ship.waypoint.x - n, ship.waypoint.y)
case (TurnRight, 90) | (TurnLeft, 270) => Position(ship.waypoint.y, -ship.waypoint.x)
case (TurnRight, 270) | (TurnLeft, 90) => Position(-ship.waypoint.y, ship.waypoint.x)
case (_, 180) => Position(-ship.waypoint.x, -ship.waypoint.y)
case _ => ship.waypoint
Ship(newDir, newPos, newWaypoint)
def forward(dir: Direction, pos: Position, amt: Int): Position = dir match
case North => Position(pos.x, pos.y + amt)
case East => Position(pos.x + amt, pos.y)
case South => Position(pos.x, pos.y - amt)
case West => Position(pos.x - amt, pos.y)
def forward2(ship: Ship, amt: Int): Position =
Position(ship.pos.x + ship.waypoint.x * amt, ship.pos.y + ship.waypoint.y * amt)
object Action:
def of(action: String): Action = action match
case "F" => GoForward
case "N" => GoNorth
case "S" => GoSouth
case "E" => GoEast
case "W" => GoWest
case "L" => TurnLeft
case "R" => TurnRight
val roundRight = Seq(North, East, South, West, North, East, South, West, North)
case class Position(x: Int, y: Int)
case class Order(action: Action, amount: Int)
case class Ship(dir: Direction, pos: Position, waypoint: Position = Position(0, 0))
type InputType = Seq[Order]
@main def _day12: Unit =
val testData = time("testReady", () => ready(testInput))
time("tesPart1", () => part1(testData)) // should be 25
time("testPart2", () => part2(testData)) // should be 286
val data = time("ready", () => ready(input))
time("part1", () => part1(data))
time("part2", () => part2(data))
private def ready(input: String): InputType =
input
.linesIterator
.map(_.splitAt(1))
.map(tuple => Order(Action.of(tuple._1), tuple._2.toInt))
.toSeq
private def part1(data: InputType): Long =
val initalShip = Ship(East, Position(0, 0))
val pos = data
.foldLeft(initalShip)((ship, order) => order.action.move(ship, order.amount))
.pos
Math.abs(pos.x) + Math.abs(pos.y)
private def part2(data: InputType): Long =
val initalShip = Ship(East, Position(0, 0), Position(10, 1))
val pos = data
.foldLeft(initalShip)((ship, order) => order.action.move2(ship, order.amount))
.pos
Math.abs(pos.x) + Math.abs(pos.y)
private val testInput =
"""F10
|N3
|F7
|R90
|F11
|""".stripMargin
private val input =
"""F12
|W1
|N3
|E3
|W3
|F93
|N2
|R90
|N4
|L180
|F13
|E2
|R270
|F16
|S4
|L90
|E1
|S4
|R180
|L90
|S2
|F89
|S3
|R90
|W1
|F2
|S2
|W3
|R180
|N2
|F41
|E3
|F74
|E1
|F20
|W3
|F32
|E1
|R90
|F19
|S4
|E1
|F41
|L180
|S1
|L90
|E5
|L90
|W2
|F45
|R180
|F17
|S3
|E2
|S1
|F27
|N5
|R180
|S1
|E5
|N1
|L270
|F60
|L180
|F18
|N2
|R180
|E4
|S4
|L180
|S5
|L270
|S1
|F32
|S5
|F83
|N2
|R180
|W1
|L180
|E2
|S3
|F94
|N3
|F82
|L90
|N2
|W5
|R180
|S4
|W3
|E1
|F81
|S3
|F45
|R90
|F51
|R180
|N1
|W5
|L90
|E3
|N5
|E3
|R180
|N3
|R180
|F87
|E4
|R90
|E4
|L180
|E4
|R90
|N1
|L270
|N3
|E3
|E3
|L180
|N1
|W5
|N3
|F85
|N1
|E2
|S3
|L90
|E5
|N3
|N1
|F74
|W2
|F79
|S1
|L90
|W5
|F88
|W4
|N1
|R180
|F94
|L90
|W5
|F79
|R180
|R270
|N3
|F83
|W3
|N3
|L90
|F33
|S5
|F93
|L90
|S1
|W3
|F24
|L90
|F80
|S2
|F86
|F7
|R90
|E1
|S3
|W3
|F23
|R90
|S1
|W4
|R90
|N4
|R270
|S1
|E1
|F20
|L270
|F31
|S2
|L180
|F41
|E3
|L90
|N3
|E3
|N1
|E5
|F27
|S3
|W2
|L90
|E5
|S1
|F9
|S3
|E2
|R90
|S5
|E2
|R180
|E3
|F32
|E3
|S1
|W1
|F39
|N4
|F5
|E5
|F26
|W4
|S1
|F54
|S5
|R90
|F50
|W4
|S1
|L90
|S5
|L90
|F2
|E5
|L90
|N1
|W3
|F75
|L90
|F85
|S2
|W4
|F93
|S4
|E3
|S2
|E4
|R90
|S3
|W1
|F94
|R90
|N3
|R270
|S2
|W3
|N5
|F1
|S1
|F32
|E2
|F17
|N4
|W2
|S4
|L90
|W2
|N2
|L180
|F94
|R90
|F78
|N3
|E3
|N3
|E4
|F37
|E5
|L180
|W2
|L180
|N2
|R270
|S2
|F28
|R90
|S1
|F15
|E1
|F50
|N3
|R90
|F14
|N4
|F80
|L90
|S5
|W1
|L90
|W5
|F100
|N1
|L90
|N5
|W2
|N1
|F76
|L180
|S3
|L180
|E1
|E5
|F1
|R90
|W4
|F95
|S2
|R90
|W2
|F29
|W2
|F47
|W5
|S5
|W4
|F58
|L90
|F22
|N1
|E4
|N4
|E2
|S5
|L180
|W4
|N2
|W3
|R90
|F76
|N1
|F41
|W5
|F48
|W1
|N4
|E2
|R180
|F79
|N1
|L90
|S4
|E2
|F86
|N2
|E1
|F5
|W4
|S2
|L90
|F3
|R270
|F43
|L180
|S5
|R90
|W5
|R180
|E4
|S3
|R90
|S2
|F41
|F70
|L270
|E4
|R90
|F18
|S4
|F88
|E2
|L90
|L270
|F56
|L90
|N1
|L90
|F7
|S3
|F36
|L90
|F2
|L90
|F2
|W4
|S4
|L90
|E5
|N2
|L90
|S4
|R90
|W1
|R90
|N2
|E3
|W2
|S4
|E4
|R90
|N5
|L90
|N4
|F55
|N3
|E1
|F80
|W2
|R90
|S2
|L90
|W5
|R90
|R90
|F87
|L270
|S5
|R270
|N5
|E5
|F10
|E1
|R180
|N1
|L90
|S3
|W1
|F18
|R90
|S3
|F89
|L90
|F42
|S3
|R180
|F92
|L90
|F48
|F11
|W2
|L180
|F27
|L180
|N3
|W1
|S2
|L90
|W1
|N1
|W4
|N1
|R90
|S2
|W5
|E1
|F74
|L180
|F48
|W3
|F3
|E3
|F74
|L270
|F38
|R180
|N2
|F83
|S1
|F78
|L90
|N4
|F43
|W3
|W2
|N1
|L90
|N2
|W4
|L90
|S5
|E5
|W1
|F83
|E5
|F70
|N2
|L90
|N2
|F66
|S2
|E2
|R90
|N1
|F2
|L90
|F15
|W3
|F10
|R90
|N3
|E5
|N5
|F57
|R90
|W2
|F83
|F91
|W5
|N2
|R90
|E4
|S2
|L90
|N2
|R90
|S1
|F49
|L90
|E3
|L180
|E2
|F98
|S1
|R180
|F23
|N2
|E2
|F8
|N2
|L90
|E2
|N4
|R90
|F29
|L90
|E5
|S3
|F92
|S5
|F68
|N1
|L90
|S5
|F73
|W4
|L180
|S1
|R180
|F74
|R90
|F27
|R180
|R90
|F88
|R270
|S1
|W1
|F73
|W1
|S5
|L90
|N5
|R90
|F50
|E2
|R90
|W3
|F23
|L90
|W2
|N1
|E2
|N2
|F56
|L90
|F22
|E5
|F46
|S2
|L180
|E4
|R90
|F10
|W2
|R90
|E5
|L270
|S4
|F55
|R90
|F17
|R90
|F8
|L180
|F25
|E4
|S2
|E1
|S1
|F35
|N5
|W5
|N3
|F79
|N1
|R90
|E1
|F32
|R90
|F87
|N2
|R180
|L180
|F38
|L90
|S1
|L270
|S5
|F63
|L180
|F50
|W1
|F23
|S2
|E2
|F30
|E3
|L90
|F79
|R180
|F90
|L180
|F81
|R90
|F72
|R180
|E4
|N3
|W3
|R90
|E5
|R90
|F81
|S3
|F66
|S5
|F83
|L90
|F15
|N5
|F16
|L270
|S3
|L270
|S3
|L90
|N5
|E2
|F60
|W2
|S4
|E1
|R180
|W2
|F28
|W4
|R90
|N3
|W3
|F48
|W2
|S5
|F2
|R90
|F47
|S5
|F11
|S5
|E2
|N2
|F93
|S2
|E4
|F23
|E4
|S1
|L90
|F87
|L180
|N4
|W5
|N5
|R180
|R90
|S5
|F65
|E5
|F51
|E5
|F65
|L90
|S4
|W3
|L180
|W1
|W2
|E4
|R270
|N4
|F86
|R90
|L90
|F9
|F76
|N4
|E4
|N4
|R90
|F40
|E5
|S1
|W3
|F22
|W2
|L90
|F51
|W1
|E1
|S2
|F27
|S5
|R90
|R270
|R90
|F71
|R90
|W4
|R90
|W1
|N4
|L90
|E2
|E1
|F61
|W1
|S5
|E2
|E4
|F10
|L90
|N2
|F3
|R90
|F7
|L90
|F56
|N1
|R270
|F70
|F71
|N3
|F96
|R90
|F56
|S4
|F96
|S5
|W5
|N4
|E2
|F90
|S5
|R180
|F81
|E1
|N4
|L90
|S2
|L180
|E5
|R90
|S4
|F60
|S4
|W3
|F3
|E5
|F54
|""".stripMargin
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