Add 2019 solutions

2019/AoC.playground/Pages/Day 14.xcplaygroundpage/Contents.swift

@@ -0,0 +1,64 @@
+import Foundation
+
+let input = """
+9 ORE => 2 A
+8 ORE => 3 B
+7 ORE => 5 C
+3 A, 4 B => 1 AB
+5 B, 7 C => 1 BC
+4 C, 1 A => 1 CA
+2 AB, 3 BC, 4 CA => 1 FUEL
+"""
+
+
+struct Chemical {
+    let name: String
+    let amount: Int
+}
+
+struct Reaction {
+    let product: Chemical
+    let educts: [Chemical]
+}
+
+var reactions: [String: Reaction] = [:]
+
+let scanner = Scanner(string: input)
+
+func parseChemical() -> Chemical? {
+    guard let amount = scanner.scanInt(),
+        let name = scanner.scanCharacters(from: .letters) else {
+            return nil
+    }
+    return Chemical(name: name, amount: amount)
+}
+
+func parseReaction() -> Reaction? {
+    var educts: [Chemical] = []
+    repeat {
+        guard let chemical = parseChemical() else {
+            return nil
+        }
+        educts.append(chemical)
+    } while scanner.scanString(",") != nil
+    guard scanner.scanString("=>") != nil else {
+        return nil
+    }
+    guard let product = parseChemical() else {
+        return nil
+    }
+
+    return Reaction(product: product, educts: educts)
+}
+
+while !scanner.isAtEnd {
+    guard let reaction = parseReaction() else {
+        fatalError()
+    }
+
+    reactions[reaction.product.name] = reaction
+}
+
+
+
+