2024 day 8

2024/day-8/day8.test.ts

@@ -0,0 +1,40 @@
+import { expect, test } from "bun:test";
+import * as path from "node:path";
+import { part1, part2 } from "./day8.ts";
+
+test("day 8, part 1", async () => {
+	const testInput = await Bun.file(
+		path.resolve(__dirname, "test-input.txt"),
+	).text();
+	const input = await Bun.file(path.resolve(__dirname, "input.txt")).text();
+
+	console.log("\n\n");
+
+	const testResult = part1(testInput);
+	console.log("Test data:", testResult);
+	expect(testResult).toEqual(14);
+
+	const finalResult = part1(input);
+	console.log("Full data:", finalResult);
+	expect(finalResult).toEqual(332);
+
+	console.log("\n\n");
+});
+
+test("day 8, part 2", async () => {
+	const testInput = await Bun.file(
+		path.resolve(__dirname, "test-input.txt"),
+	).text();
+	const input = await Bun.file(path.resolve(__dirname, "input.txt")).text();
+
+	const testResult = part2(testInput);
+	console.log("\n\n");
+	console.log("Test data:", testResult);
+	expect(testResult).toEqual(34);
+
+	const finalResult = part2(input);
+	console.log("Full data:", finalResult);
+	expect(finalResult).toEqual(1174);
+
+	console.log("\n\n");
+});

2024/day-8/day8.ts

@@ -0,0 +1,186 @@
+export function part1(input: string) {
+	const lines = input.split("\n");
+	const height = lines.length;
+	const width = lines[0].length;
+	const antennas = new Map();
+	for (let i = 0; i < lines.length; i++) {
+		const line = lines[i];
+		for (let j = 0; j < line.length; j++) {
+			const char = line[j];
+			if (char === ".") {
+				continue;
+			}
+			const [x, y] = [i, j];
+			if (antennas.has(char)) {
+				const current = antennas.get(char);
+
+				current.push([x, y]);
+			} else {
+				antennas.set(char, [[x, y]]);
+			}
+		}
+	}
+
+	const antinodes = [];
+	for (const frequency of antennas.keys()) {
+		const antennasOnFreq = antennas.get(frequency);
+		for (let i = 0; i < antennasOnFreq.length; i++) {
+			for (let j = i + 1; j < antennasOnFreq.length; j++) {
+				const p1 = antennasOnFreq[i];
+				const p2 = antennasOnFreq[j];
+				const distanceX = Math.abs(p1[0] - p2[0]);
+				const distanceY = Math.abs(p1[1] - p2[1]);
+				const antinode1 = [];
+				const antinode2 = [];
+
+				if (p1[0] > p2[0]) {
+					antinode1[0] = p1[0] + distanceX;
+					antinode2[0] = p2[0] - distanceX;
+				} else {
+					antinode1[0] = p1[0] - distanceX;
+					antinode2[0] = p2[0] + distanceX;
+				}
+
+				if (p1[1] > p2[1]) {
+					antinode1[1] = p1[1] + distanceY;
+					antinode2[1] = p2[1] - distanceY;
+				} else {
+					antinode1[1] = p1[1] - distanceY;
+					antinode2[1] = p2[1] + distanceY;
+				}
+				if (
+					!(
+						antinode1[0] < 0 ||
+						antinode1[0] >= height ||
+						antinode1[1] < 0 ||
+						antinode1[1] >= width
+					)
+				) {
+					antinodes.push(antinode1);
+				}
+				if (
+					!(
+						antinode2[0] < 0 ||
+						antinode2[0] >= height ||
+						antinode2[1] < 0 ||
+						antinode2[1] >= width
+					)
+				) {
+					antinodes.push(antinode2);
+				}
+			}
+		}
+	}
+	const uniqueAntinodes = [...new Set(antinodes.map((x) => x.join(",")))].map(
+		(x) => x.split(","),
+	);
+
+	return uniqueAntinodes.length;
+}
+
+export function part2(input: string) {
+	const lines = input.split("\n");
+	const height = lines.length;
+	const width = lines[0].length;
+	const antennas = new Map();
+	for (let i = 0; i < lines.length; i++) {
+		const line = lines[i];
+		for (let j = 0; j < line.length; j++) {
+			const char = line[j];
+			if (char === ".") {
+				continue;
+			}
+			const [x, y] = [i, j];
+			if (antennas.has(char)) {
+				const current = antennas.get(char);
+
+				current.push([x, y]);
+			} else {
+				antennas.set(char, [[x, y]]);
+			}
+		}
+	}
+
+	const antinodes: [number, number][] = [];
+	for (const frequency of antennas.keys()) {
+		const antennasOnFreq = antennas.get(frequency);
+		for (let i = 0; i < antennasOnFreq.length; i++) {
+			for (let j = i + 1; j < antennasOnFreq.length; j++) {
+				const p1 = antennasOnFreq[i];
+				const p2 = antennasOnFreq[j];
+				const distanceX = Math.abs(p1[0] - p2[0]);
+				const distanceY = Math.abs(p1[1] - p2[1]);
+				antinodes.push(p1, p2);
+				if (p1[0] < p2[0] && p1[1] < p2[1]) {
+					let nextX = p2[0];
+					let nextY = p2[1];
+					while (true) {
+						nextX = nextX + distanceX;
+						nextY = nextY + distanceY;
+
+						if (nextX >= 0 && nextX < height && nextY >= 0 && nextY < width) {
+							antinodes.push([nextX, nextY]);
+						} else {
+							break;
+						}
+					}
+					let prevX = p2[0];
+					let prevY = p2[1];
+					while (true) {
+						prevX = prevX - distanceX;
+						prevY = prevY - distanceY;
+
+						if (prevX >= 0 && prevX < height && prevY >= 0 && prevY < width) {
+							antinodes.push([prevX, prevY]);
+						} else {
+							break;
+						}
+					}
+				} else if (p1[0] < p2[0] && p1[1] > p2[1]) {
+					let nextX = p2[0];
+					let nextY = p2[1];
+					while (true) {
+						nextX = nextX - distanceX;
+						nextY = nextY + distanceY;
+
+						if (nextX >= 0 && nextX < height && nextY >= 0 && nextY < width) {
+							antinodes.push([nextX, nextY]);
+						} else {
+							break;
+						}
+					}
+					let prevX = p2[0];
+					let prevY = p2[1];
+					while (true) {
+						prevX = prevX + distanceX;
+						prevY = prevY - distanceY;
+
+						if (prevX >= 0 && prevX < height && prevY >= 0 && prevY < width) {
+							antinodes.push([prevX, prevY]);
+						} else {
+							break;
+						}
+					}
+				}
+			}
+		}
+	}
+	const uniqueAntinodes = [...new Set(antinodes.map((x) => x.join(",")))].map(
+		(x) => x.split(","),
+	);
+
+	// display(lines, uniqueAntinodes);
+
+	return uniqueAntinodes.length;
+}
+
+function display(lines: string[], antinodes: string[][]) {
+	const nl = lines.map((x) => x.split(""));
+
+	for (const u of antinodes) {
+		nl[u[0]][u[1]] === "." ? (nl[u[0]][u[1]] = "#") : null;
+	}
+	for (const x of nl) {
+		console.log(x.join(""));
+	}
+}

2024/day-8/input.txt

@@ -0,0 +1,50 @@
+................n................L..Y.............
+........m.........................................
+.............n.............................l......
+...............T.m..e....M........................
+...........T..y...........i.......L.....2.........
+.....................e.....h.......Y........l.....
+...................i......d.......................
+...5..............T....o......i...................
+......C.5...........m..p...o.........2....I.......
+.......C.n...........d..............o....p........
+..............e........dp.....M...................
+..8.........w.N.....n.p.....F.....................
+.......N.......m.....D....o.......................
+........DU...........y.........I..................
+..D..X......N.T....M..............................
+...........D..............2c..hl.A....M...........
+.5.w.8...............h6...........................
+5.....P...............d.Y.y......FA......L........
+........w.................h.......................
+...................N..............................
+.............B...............u.f..................
+.........wX.......6...............................
+..............XC..............Ax..................
+.P.......8......................c........f........
+...e....U.u.........s.........f............Y......
+..........U..X.........2..........W.....f.........
+........P.........................................
+.........s.u......................S...............
+.....U...................c.....F............H.....
+.........BC..........6............................
+...................s..7..A...S............3I......
+........B.s...u............S...i........H.........
+..O.........................c....W....S...........
+..........................a..........3......IE....
+0........P................F.......................
+.............7.................W........3.........
+......t.W............7........................E...
+...O.....9............................E...........
+.....a19..........................................
+....t.......O..........x..........................
+..................................b..............3
+........1......................b..................
+.......1....8...........x.........................
+.......40.........................................
+.....t...O.0...4...........................H......
+.......0..............x.......b...................
+..4.......a.B..............b...........6..........
+.......t9..........17..................H..........
+........................9.........................
+...........a......................................

2024/day-8/test-input-2.txt

@@ -0,0 +1,12 @@
+......#....#
+...#....0...
+....#0....#.
+..#....0....
+....0....#..
+.#....#.....
+...#........
+#......#....
+........A...
+.........A..
+..........#.
+..........#.

2024/day-8/test-input.txt

@@ -0,0 +1,12 @@
+............
+........0...
+.....0......
+.......0....
+....0.......
+......A.....
+............
+............
+........A...
+.........A..
+............
+............

package.json

@@ -2,6 +2,9 @@
 	"name": "advent-of-code",
 	"module": "index.ts",
 	"type": "module",
+	"scripts": {
+		"prepare": "bun run scripts/prepare.ts"
+	},
 	"devDependencies": {
 		"@biomejs/biome": "1.9.4",
 		"@types/bun": "latest"

scripts/prepare.ts

@@ -0,0 +1,74 @@
+import * as path from "node:path";
+import { $ } from "bun";
+async function prepare(day: number, year?: number) {
+	const currentYear = year ?? new Date().getFullYear();
+	const fileName = `day${day}.ts`;
+	const testFileName = `day${day}.test.ts`;
+	const dir = path.join(__dirname, "..", currentYear.toString(), `day-${day}`);
+	console.log(`Preparing ${dir}`);
+	const codeTemplate = `
+        export function part1(input: string) {
+            const lines = input.split("\\n");
+            let final = 0;
+            return final;
+        }
+        
+         export function part2(input: string) {
+            const lines = input.split("\\n");
+            let final = 0;
+            return final;
+        }
+    `.trim();
+
+	const testTemplate = `
+	import { expect, test } from "bun:test";
+    import * as path from "node:path";
+    import { part1, part2 } from "./${fileName}";
+
+    test("day ${day}, part 1", async () => {
+        const testInput = await Bun.file(
+            path.resolve(__dirname, "test-input.txt"),
+        ).text();
+        const input = await Bun.file(path.resolve(__dirname, "input.txt")).text();
+    
+        console.log("\\n\\n");
+    
+        const testResult = part1(testInput);
+        console.log("Test data:", testResult);
+        expect(testResult).toEqual(0);
+    
+        // const finalResult = part1(input);
+        // console.log("Full data:", finalResult);
+        // expect(finalResult).toEqual(0);
+    
+        console.log("\\n\\n");
+    });
+
+    test("day ${day}, part 2", async () => {
+        const testInput = await Bun.file(
+        path.resolve(__dirname, "test-input.txt"),
+        ).text();
+        const input = await Bun.file(path.resolve(__dirname, "input.txt")).text();
+    
+        const testResult = part2(testInput);
+        console.log("\\n\\n");
+        console.log("Test data:", testResult);
+        expect(testResult).toEqual(0);
+        
+        // const finalResult = part2(input);
+        // console.log("Full data:", finalResult);
+        // expect(finalResult).toEqual(0);
+    
+        console.log("\\n\\n");
+    });
+    `;
+
+	await Bun.write(path.join(dir, testFileName), testTemplate);
+	await Bun.write(path.join(dir, fileName), codeTemplate);
+	await Bun.write(path.join(dir, "test-input.txt"), "");
+	await Bun.write(path.join(dir, "input.txt"), "");
+	console.log(await $`bunx biome check --write ${dir}`.text());
+}
+
+const [_, __, day, year] = process.argv;
+void prepare(Number(day), year ? Number(year) : undefined);