2023 - Day 2

2023/02/solution.ts

@@ -0,0 +1,71 @@
+const sample = await Deno.readTextFile("sample.txt");
+const input = await Deno.readTextFile("input.txt");
+
+type Game = {
+  number: number;
+  highest: Draw;
+  draws: Draw[];
+};
+
+interface Draw {
+  blue: number;
+  red: number;
+  green: number;
+}
+
+const parseDraws = (draw: string): Draw =>
+  draw.split(", ").map((cube) => (cube.match(/^(\d+)\ (\w+)$/) || []))
+    .reduce(
+      (draw, [_, amount, color]): Draw => ({
+        ...draw,
+        [color]: parseFloat(amount),
+      }),
+      { blue: 0, red: 0, green: 0 },
+    );
+
+const parseGame = (game: string, index: number): Game => {
+  const draws = (game
+    .split(": ")
+    .pop() ?? "")
+    .split("; ")
+    .map(parseDraws);
+
+  const highest = {
+    green: draws.reduce((max, d) => Math.max(d.green, max), 0),
+    blue: draws.reduce((max, d) => Math.max(d.blue, max), 0),
+    red: draws.reduce((max, d) => Math.max(d.red, max), 0),
+  };
+
+  return ({
+    number: index + 1,
+    highest,
+    draws,
+  });
+};
+
+const solvePart1 = (data: string, match: Draw): number =>
+  data
+    .split("\n")
+    .filter(Boolean)
+    .map(parseGame)
+    .filter((game) =>
+      game.highest.blue <= match.blue && game.highest.green <= match.green &&
+      game.highest.red <= match.red
+    )
+    .reduce((sum, { number }) => sum + number, 0);
+
+console.log("Sample:", solvePart1(sample, { red: 12, green: 13, blue: 14 })); // 8
+console.log("Input", solvePart1(input, { red: 12, green: 13, blue: 14 })); // 2101
+
+const solvePart2 = (data: string): number =>
+  data
+    .split("\n")
+    .filter(Boolean)
+    .map(parseGame)
+    .reduce(
+      (sum, { highest }) => sum + (highest.blue * highest.green * highest.red),
+      0,
+    );
+
+console.log("Sample2:", solvePart2(sample)); // 2286
+console.log("Input", solvePart2(input)); // 58269