feat: solved 2023 day 15

.github/badges/typescript/2023.json

@@ -1,6 +1,6 @@
 {
 	"schemaVersion": 1,
 	"label": "Advent of TypeScript 2023",
-	"message": "12/25",
+	"message": "13/25",
 	"color": "orange"
 }

resources/2023/15/example.1.txt

@@ -0,0 +1 @@
+rn=1,cm-,qp=3,cm=2,qp-,pc=4,ot=9,ab=5,pc-,pc=6,ot=7

solutions/typescript/2023/15/src/internal/hash.spec.ts

@@ -0,0 +1,8 @@
+import { describe, expect, it } from 'vitest';
+import { hash } from './hash.js';
+
+describe('hash', () => {
+	it('should, return for the string hash', () => {
+		expect(hash('HASH')).toEqual(52);
+	});
+});

solutions/typescript/2023/15/src/internal/hash.ts

@@ -0,0 +1,9 @@
+export const hash = (s: string): number => {
+	let value = 0;
+	for (let i = 0; i < s.length; i++) {
+		value += s.codePointAt(i) ?? 0;
+		value *= 17;
+		value %= 256;
+	}
+	return value;
+};

solutions/typescript/2023/15/src/internal/parse.ts

@@ -0,0 +1,42 @@
+import { hash } from './hash.js';
+
+interface SetInstruction {
+	label: string;
+	box: number;
+	operator: '=';
+	focalLength: number;
+}
+
+interface RemoveInstruction {
+	label: string;
+	box: number;
+	operator: '-';
+}
+
+type Instruction = SetInstruction | RemoveInstruction;
+
+const instructionRegex = /(.*)([=-])(.*)/;
+
+export const parseInstruction = (instruction: string): Instruction => {
+	const match = instructionRegex.exec(instruction);
+	if (!match) {
+		throw new Error('instruction not matching regex: ' + instruction);
+	}
+	const [, label, operator, value] = match;
+	if (operator === '=' && value !== undefined && label !== undefined) {
+		return {
+			focalLength: Number.parseInt(value, 10),
+			label,
+			operator,
+			box: hash(label),
+		};
+	} else if (operator === '-' && label !== undefined) {
+		return {
+			label,
+			operator,
+			box: hash(label),
+		};
+	} else {
+		throw new Error('invalid instruction: ' + instruction);
+	}
+};

solutions/typescript/2023/15/src/p1.spec.ts

@@ -7,14 +7,14 @@ describe('2023 15 p1', () => {
 	describe('the input', () => {
 		it('should solve the input', async () => {
 			const resources = await loadTaskResources(packageJson.aoc);
-			expect(p1(resources.input)).toEqual(0);
+			expect(p1(resources.input)).toEqual(495_972);
 		});
 	});
 
 	describe('example 1', () => {
 		it('should be solved', async () => {
 			const resources = await loadTaskResources(packageJson.aoc, 'example.1.txt');
-			expect(p1(resources.input)).toEqual(0);
+			expect(p1(resources.input)).toEqual(1320);
 		});
 	});
 });

solutions/typescript/2023/15/src/p1.ts

@@ -1,8 +1,7 @@
 import { task } from '@alexaegis/advent-of-code-lib';
 import packageJson from '../package.json';
+import { hash } from './internal/hash.js';
 
-export const p1 = (_input: string): number => {
-	return 0;
-};
+export const p1 = (input: string): number => input.lines(false).first().split(',').map(hash).sum();
 
-await task(p1, packageJson.aoc); // 0 ~0ms
+await task(p1, packageJson.aoc); // 495972 ~0.19ms

solutions/typescript/2023/15/src/p2.spec.ts

@@ -7,14 +7,14 @@ describe('2023 15 p2', () => {
 	describe('the input', () => {
 		it('should solve the input', async () => {
 			const { input } = await loadTaskResources(packageJson.aoc);
-			expect(p2(input)).toEqual(0);
+			expect(p2(input)).toEqual(245_223);
 		});
 	});
 
 	describe('example 1', () => {
 		it('should be solved', async () => {
 			const { input } = await loadTaskResources(packageJson.aoc, 'example.1.txt');
-			expect(p2(input)).toEqual(0);
+			expect(p2(input)).toEqual(145);
 		});
 	});
 });

solutions/typescript/2023/15/src/p2.ts

@@ -1,8 +1,42 @@
 import { task } from '@alexaegis/advent-of-code-lib';
 import packageJson from '../package.json';
+import { parseInstruction } from './internal/parse.js';
 
-export const p2 = (_input: string): number => {
-	return 0;
+interface Lens {
+	label: string;
+	focalLength: number;
+}
+
+export const p2 = (input: string): number => {
+	const sequence = input.lines(false).first().split(',').map(parseInstruction);
+	const boxMap = new Map<number, Lens[]>();
+
+	for (const instruction of sequence) {
+		if (instruction.operator === '-') {
+			const lenses = boxMap.get(instruction.box);
+			const lenseIndex = lenses?.findIndex((lens) => lens.label === instruction.label) ?? -1;
+			if (lenses !== undefined && lenseIndex >= 0) {
+				lenses.splice(lenseIndex, 1);
+				if (lenses.length === 0) {
+					boxMap.delete(instruction.box);
+				}
+			}
+		} else {
+			const lenses = boxMap.getOrAdd(instruction.box, (_key) => []);
+			const existingLens = lenses.find((lens) => lens.label === instruction.label);
+			if (existingLens) {
+				existingLens.focalLength = instruction.focalLength;
+			} else {
+				lenses.push({ focalLength: instruction.focalLength, label: instruction.label });
+			}
+		}
+	}
+
+	return [...boxMap.entries()]
+		.flatMap(([box, lenses]) =>
+			lenses.map((lens, lenseIndex) => (box + 1) * (lenseIndex + 1) * lens.focalLength),
+		)
+		.sum();
 };
 
-await task(p2, packageJson.aoc); // 0 ~0ms
+await task(p2, packageJson.aoc); // 245223 ~0.65ms

solutions/typescript/readme.md

@@ -20,9 +20,9 @@
 | [Day 10](/solutions/typescript/2023/10/) | [68.44ms](/solutions/typescript/2023/10/src/p1.ts)  | [1.4s](/solutions/typescript/2023/10/src/p2.ts)     |
 | [Day 11](/solutions/typescript/2023/11/) | [104.54ms](/solutions/typescript/2023/11/src/p1.ts) | [104.48ms](/solutions/typescript/2023/11/src/p2.ts) |
 | [Day 12](/solutions/typescript/2023/12/) | [30.83ms](/solutions/typescript/2023/12/src/p1.ts)  | [539.06ms](/solutions/typescript/2023/12/src/p2.ts) |
-| Day 13                                   | -                                                   | -                                                   |
-| Day 14                                   | -                                                   | -                                                   |
-| Day 15                                   | -                                                   | -                                                   |
+| [Day 13](/solutions/typescript/2023/13/) | [?ms](/solutions/typescript/2023/13/src/p1.ts)      | [?ms](/solutions/typescript/2023/13/src/p2.ts)      |
+| [Day 14](/solutions/typescript/2023/14/) | [?ms](/solutions/typescript/2023/14/src/p1.ts)      | [?ms](/solutions/typescript/2023/14/src/p2.ts)      |
+| [Day 15](/solutions/typescript/2023/15/) | [0.19ms](/solutions/typescript/2023/15/src/p1.ts)   | [0.65ms](/solutions/typescript/2023/15/src/p2.ts)   |
 | Day 16                                   | -                                                   | -                                                   |
 | Day 17                                   | -                                                   | -                                                   |
 | Day 18                                   | -                                                   | -                                                   |