From 3adab989c286637b32df3e28b62ffc42b8fc9477 Mon Sep 17 00:00:00 2001
From: Dory <dory@dory.moe>
Date: Thu, 19 Dec 2024 08:42:56 -0800
Subject: [PATCH] make d19p2 shorter

---
 day19/d19p2.swift | 28 ++++++++--------------------
 1 file changed, 8 insertions(+), 20 deletions(-)

diff --git a/day19/d19p2.swift b/day19/d19p2.swift
index d55b029..c641b69 100644
--- a/day19/d19p2.swift
+++ b/day19/d19p2.swift
@@ -1,37 +1,25 @@
 import Foundation
 
-enum Color: Character, CustomStringConvertible {
-    case r = "r"
-    case g = "g"
-    case u = "u"
-    case w = "w"
-    case b = "b"
-    var description: String { return String(self.rawValue) }
-}
+typealias Color = Character
 
 func readInput(_ filePath: String) throws -> ([[Color]], [[Color]]) {
     let content = try String(contentsOfFile: filePath, encoding: .ascii)
     let lines = content.split(separator: "\n")
-    let towels = lines[0].split(separator: ", ").map { $0.compactMap(Color.init) }
-    let patterns = lines[1..<lines.count].map { $0.compactMap(Color.init) }
+    let towels = lines[0].split(separator: ", ").map(Array.init)
+    let patterns = lines[1..<lines.count].map(Array.init)
     return (towels, patterns)
 }
 
 var cache: [[Color]: Int] = [:]
 func matches(_ pattern: [Color], _ towels: [[Color]]) -> Int {
-    if pattern.count == 0 {
-        return 1
-    }
-    if let cached = cache[pattern] {
-        return cached
-    }
-    let r = towels
+    if pattern.count == 0 { return 1 }
+    if let cached = cache[pattern] { return cached }
+    cache[pattern] = towels
         .filter { pattern.starts(with: $0) }
         .map { matches(Array(pattern[$0.count..<pattern.count]), towels) }
         .reduce(0, +)
-    cache[pattern] = r
-    return r
+    return cache[pattern]!
 }
 
 let (towels, patterns) = try readInput(CommandLine.arguments[1])
-print(patterns.reduce(0) { s, p in s + matches(p, towels) })
+print(patterns.map{ matches($0, towels) }.reduce(0, +))