Some optimisations

Package.swift

@@ -24,7 +24,9 @@ let package = Package(
             .executable(name: "12", targets: ["12"]),
             .executable(name: "13", targets: ["13"]),
             .executable(name: "14", targets: ["14"]),
-            .executable(name: "15", targets: ["15"])
+            .executable(name: "15", targets: ["15"]),
+            .executable(name: "16", targets: ["16"]),
+            .executable(name: "17", targets: ["17"])
         ],
     dependencies: [
         // Dependencies declare other packages that this package depends on.
@@ -112,12 +114,20 @@ let package = Package(
         .executableTarget(
             name: "14",
             dependencies: [ .targetItem(name: "Runner", condition: nil) ]
-        )
-        ,
+        ),
         .executableTarget(
             name: "15",
             dependencies: [ .targetItem(name: "Runner", condition: nil),
                             .product(name: "Collections", package: "swift-collections")]
+        ),
+        .executableTarget(
+            name: "16",
+            dependencies: [ .targetItem(name: "Runner", condition: nil) ]
+        ),
+        .executableTarget(
+            name: "17",
+            dependencies: [ .targetItem(name: "Runner", condition: nil),
+                            .product(name: "Collections", package: "swift-collections")]
         )
     ]
 )

Sources/15/15.swift

@@ -38,22 +38,11 @@ class Day15: Runnable {
         self.inputPath = inputPath
     }
     
-    public func run() {
-        let input = try! String(contentsOfFile: inputPath)
-        parts = input
-            .trimmingCharacters(in: .newlines)
-            .components(separatedBy: .newlines)
-            .map { Array($0) }
-            .map { ar in ar.map {c in ThreatLevel(c.description)!} }
-        lastRow = parts.count - 1
-        lastCol = (parts.first?.count ?? 0) - 1
-        
+    private func expandMap() {
         var tmpParts = parts
         for (rowNum, row) in tmpParts.enumerated() {
             let newRow = [Int](0...4).flatMap { cr in
-                row
-                    .map { rv in cr + rv }
-                    .map { $0 > 9 ? $0 - 9 : $0 }
+                row.map { rv in cr + rv }.map { $0 > 9 ? $0 - 9 : $0 }
             }
             parts[rowNum] = newRow
         }
@@ -69,7 +58,25 @@ class Day15: Runnable {
         
         lastRow = parts.count - 1
         lastCol = (parts.first?.count ?? 0) - 1
+    }
+    
+    public func run() {
+        let input = try! String(contentsOfFile: inputPath)
+        parts = input
+            .trimmingCharacters(in: .newlines)
+            .components(separatedBy: .newlines)
+            .map { Array($0) }
+            .map { ar in ar.map {c in ThreatLevel(c.description)!} }
+        lastRow = parts.count - 1
+        lastCol = (parts.first?.count ?? 0) - 1
         
+        calculateSafestPath()
+        expandMap()
+        neighbors = [Coord: [Coord]]()
+        calculateSafestPath()
+    }
+    
+    private func calculateSafestPath() {
         // Distances to startNode
         var totalThreatLevel = [Coord: ThreatLevel]()
         
@@ -78,6 +85,13 @@ class Day15: Runnable {
                 Coord(row: row.offset, col: col)
             }
         })
+        
+        /* Keep a seperate dictionary, to calculate which coordinates have a set threat level
+         * a.k.a total distance to start
+         * This allows to find the next coordinate to check fairly quickly, by just
+         * looking at the minmum key in this.
+         * I initially tried a PriorityQueue, but my implementation was pretty slow and it spent too much time sorting
+         */
         var threatLevelDistrubution = [ThreatLevel: Set<Coord>]()
         let startNode = Coord(row: 0, col: 0)
         totalThreatLevel[startNode] = 0
@@ -89,6 +103,8 @@ class Day15: Runnable {
             let currentNode = threatLevelDistrubution[threatLevel]!.first!
             unvisited.remove(currentNode)
             threatLevelDistrubution[threatLevel]!.remove(currentNode)
+            
+            // Remove key from dictionary if not coords are left for a specific threat level
             if threatLevelDistrubution[threatLevel]!.isEmpty {
                 threatLevelDistrubution.removeValue(forKey: threatLevel)
             }
@@ -114,6 +130,8 @@ class Day15: Runnable {
                     totalThreatLevel[a] = testCost
                     threatLevelDistrubution[currentCost]!.remove(a)
                     threatLevelDistrubution[testCost, default: Set<Coord>()].insert(a)
+                    
+                    // Remove key from dictionary if not coords are left for a specific threat leveli
                     if threatLevelDistrubution[currentCost]!.isEmpty {
                         threatLevelDistrubution.removeValue(forKey: currentCost)
                     }

Sources/16/16.swift

@@ -0,0 +1,191 @@
+//
+//  File.swift
+//
+//
+//  Created by Max Nuding on 15.12.21.
+//
+
+import Foundation
+import Runner
+
+
+enum OperatorType: Int {
+    case sum = 0
+    case product = 1
+    case minimum = 2
+    case maximum = 3
+    case value = 4
+    case greaterThan = 5
+    case lessThan = 6
+    case equal = 7
+}
+
+protocol Packet {
+    var version: Int { get }
+    
+    func getTotalVersion() -> Int
+    func getValue() -> Int
+}
+
+struct ValuePacket: Packet {
+    let version: Int
+    let value: Int
+    
+    func getTotalVersion() -> Int { version }
+    func getValue() -> Int { value }
+}
+
+struct OperatorPacket: Packet {
+    let type: OperatorType
+    let version: Int
+    let subPackets: [Packet]
+    
+    func getTotalVersion() -> Int { version + subPackets.map { $0.getTotalVersion() }.reduce(0, +) }
+    func getValue() -> Int {
+        let spValues = subPackets.map { $0.getValue() }
+        switch type {
+        case .sum:
+            return spValues.reduce(0, +)
+        case .product:
+            return spValues.reduce(1, *)
+        case .minimum:
+            return spValues.min()!
+        case .maximum:
+            return spValues.max()!
+        case .greaterThan:
+            return spValues.first! > spValues.last! ? 1 : 0
+        case .lessThan:
+            return spValues.first! < spValues.last! ? 1 : 0
+        case .equal:
+            return spValues.first! == spValues.last! ? 1 : 0
+        case .value:
+            fatalError()
+        }
+    }
+}
+
+class Day16: Runnable {
+    let inputPath: String
+    
+    required init(inputPath: String) {
+        self.inputPath = inputPath
+    }
+    
+    public func run() {
+        let input = try! String(contentsOfFile: inputPath)
+        let parts = input
+            .trimmingCharacters(in: .newlines)
+        let bytes = parts.bits().joined()
+        let packets = parsePacket(bytes: bytes)
+        let p: Packet = packets.0
+        print(p.getTotalVersion())
+        print(p.getValue())
+    }
+    
+    func parsePacket<S>(bytes: S) -> (Packet, S.SubSequence) where S:StringProtocol {
+        let version = bytes[bytes.startIndex..<bytes.index(bytes.startIndex, offsetBy: 3)].binaryToDecimal()
+        let typeId = bytes[bytes.index(bytes.startIndex, offsetBy: 3)..<bytes.index(bytes.startIndex, offsetBy: 6)].binaryToDecimal()
+        var value: Packet
+        var reminder: S.SubSequence
+        switch typeId {
+        case 4:
+            let (v, r) = parseLiteralPacketValue(bytes: bytes)
+            value = ValuePacket(version: version, value: v)
+            reminder = r
+        default:
+            let (v, r) = parseOperatorPacker(bytes: bytes)
+            value = OperatorPacket(type: OperatorType(rawValue: typeId)!, version: version, subPackets: v)
+            reminder = r
+        }
+        return (value, reminder)
+    }
+    
+    func parseOperatorPacker<S>(bytes: S) -> ([Packet], S.SubSequence) where S:StringProtocol  {
+        let startNextBitsIndex = bytes.index(bytes.startIndex, offsetBy: 7)
+        let lengthTypeId = bytes[bytes.index(bytes.startIndex, offsetBy: 6)..<startNextBitsIndex].description
+        let isTotalLength = lengthTypeId == "0"
+        
+        let nextBitsLength = isTotalLength ? 15 : 11
+        let endNextBitsIndex = bytes.index(startNextBitsIndex, offsetBy: nextBitsLength)
+        let nextBits = bytes[startNextBitsIndex..<endNextBitsIndex]
+        
+        var number = nextBits.binaryToDecimal()
+        var reminder = bytes[endNextBitsIndex...]
+        var subPackets = [Packet]()
+        
+        while number > 0 {
+            let (p, rem) = parsePacket(bytes: reminder)
+            number -= isTotalLength ? (reminder.count - rem.count) : 1
+            subPackets.append(p)
+            reminder = rem
+        }
+        return (subPackets, reminder)
+    }
+    
+    func parseLiteralPacketValue<S>(bytes: S) -> (Int, S.SubSequence) where S:StringProtocol  {
+        var index = bytes.index(bytes.startIndex, offsetBy: 6)
+        var ei = index
+        var bits: Substring = ""
+        var reminder: S.SubSequence = ""
+        while true {
+            let si = bytes.index(index, offsetBy: 1)
+            ei = bytes.index(si, offsetBy: 4)
+            bits += bytes[si..<ei]
+            if bytes[index] == "0" {
+                reminder = bytes[ei...]
+                break
+            }
+            index = bytes.index(ei, offsetBy: 0)
+        }
+        return (bits.binaryToDecimal(), reminder)
+    }
+}
+
+extension StringProtocol {
+    func bits() -> [String] {
+        self.map { $0.bits }
+    }
+    
+    func binaryToDecimal() -> Int { Int(self, radix: 2)! }
+}
+
+extension Character {
+    var bits: String  {
+        switch self.hexDigitValue! {
+        case 0:
+            return "0000"
+        case 1:
+            return "0001"
+        case 2:
+            return "0010"
+        case 3:
+            return "0011"
+        case 4:
+            return "0100"
+        case 5:
+            return "0101"
+        case 6:
+            return "0110"
+        case 7:
+            return "0111"
+        case 8:
+            return "1000"
+        case 9:
+            return "1001"
+        case 10:
+            return "1010"
+        case 11:
+            return "1011"
+        case 12:
+            return "1100"
+        case 13:
+            return "1101"
+        case 14:
+            return "1110"
+        case 15:
+            return "1111"
+        default:
+            fatalError()
+        }
+    }
+}

Sources/16/main.swift

@@ -0,0 +1,12 @@
+//
+//  File.swift
+//  
+//
+//  Created by Max Nuding on 15.12.21.
+//
+
+import Foundation
+import Runner
+
+//Runner(target: Day16.self, day: "16", isTest: true).run()
+Runner(target: Day16.self, day: "16", isTest: false).run()

Sources/17/17.swift

@@ -0,0 +1,95 @@
+//
+//  File.swift
+//
+//
+//  Created by Max Nuding on 17.12.21.
+//
+
+import Foundation
+import Runner
+import Collections
+
+struct Point:Hashable {
+    var x: Int
+    var y: Int
+}
+
+struct Area {
+    let topLeft: Point
+    let botRight: Point
+    
+    init(x: String, y: String) {
+        let xVals = x[x.index(x.startIndex, offsetBy: 2)...].components(separatedBy: "..").map { Int($0)! }
+        let yVals = y[y.index(y.startIndex, offsetBy: 2)...].components(separatedBy: "..").map { Int($0)! }
+        topLeft = Point(x: xVals.first!, y: yVals.last!)
+        botRight = Point(x: xVals.last!, y: yVals.first!)
+    }
+    
+    func contains(point: Point) -> Bool {
+        point.x >= topLeft.x && point.x <= botRight.x && point.y <= topLeft.y && point.y >= botRight.y
+    }
+    
+    func overshot(point: Point) -> Bool {
+        point.y < botRight.y || point.x > botRight.x
+    }
+}
+
+struct Probe {
+    var position = Point(x: 0, y: 0)
+    var velocity: Point
+    
+    mutating func move() {
+        position.x += velocity.x
+        position.y += velocity.y
+        if velocity.x < 0 {
+            velocity.x += 1
+        } else if velocity.x > 0 {
+            velocity.x -= 1
+        }
+        velocity.y -= 1
+    }
+}
+
+class Day17: Runnable {
+    let inputPath: String
+    
+    required init(inputPath: String) {
+        self.inputPath = inputPath
+    }
+    
+    public func run() {
+        let input = try! String(contentsOfFile: inputPath)
+        let parts = input
+            .trimmingCharacters(in: .newlines)
+            .components(separatedBy: ": ")
+            .last!
+            .components(separatedBy: ", ")
+        let area = Area(x: parts.first!, y: parts.last!)
+        
+        var maxY = Int.min
+        var found = [Point]()
+        found.reserveCapacity(3000)
+        for x in 0...500 {
+            for y in -500...500 {
+                let velocity = Point(x: x, y: y)
+                var probe = Probe(velocity: velocity)
+                var maxYCurrent = Int.min
+                repeat {
+                    probe.move()
+                    if probe.position.y > maxYCurrent {
+                        maxYCurrent = probe.position.y
+                    }
+                    if area.contains(point: probe.position) {
+                        if maxYCurrent > maxY {
+                            maxY = maxYCurrent
+                        }
+                        found.append(velocity)
+                        break
+                    }
+                } while !area.overshot(point: probe.position)
+            }
+        }
+        print(maxY)
+        print(Set(found).count)
+    }
+}

Sources/17/main.swift

@@ -0,0 +1,12 @@
+//
+//  File.swift
+//  
+//
+//  Created by Max Nuding on 17.12.21.
+//
+
+import Foundation
+import Runner
+
+//Runner(target: Day17.self, day: "17", isTest: true).run()
+Runner(target: Day17.self, day: "17", isTest: false).run()

Sources/Runner/Resources/input/16.txt

@@ -0,0 +1 @@
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

Sources/Runner/Resources/input/16_test.txt

@@ -0,0 +1 @@
+38006F45291200

Sources/Runner/Resources/input/17.txt

@@ -0,0 +1 @@
+target area: x=128..160, y=-142..-88

Sources/Runner/Resources/input/17_test.txt

@@ -0,0 +1 @@
+target area: x=20..30, y=-10..-5