advent_of_code_2023/Day04/ts/solution.ts
2023-12-15 22:46:01 +01:00

86 lines
2.1 KiB
TypeScript

import { readFileSync } from "fs";
function main() {
try {
console.log("Running tests...");
runTest("../test.txt");
console.log("Tests passed.");
console.log("Processing main input...");
const result = processInput("../input.txt");
console.log(`Puzzle result: ${result}`);
} catch (error) {
console.error(`Error: ${error}`);
}
}
function runTest(filename: string) {
const input = readFile(filename);
const cards = parse(input);
const partAResult = partA(cards);
const partBResult = partB(cards);
console.assert(partAResult === 13, `Part A Test failed: Expected 13, got ${partAResult}`);
console.assert(partBResult === 30, `Part B Test failed: Expected 30, got ${partBResult}`);
}
function processInput(filename: string): number {
const input = readFile(filename);
const cards = parse(input);
return partA(cards) + partB(cards);
}
function partA(cards: Card[]): number {
return cards
.filter(card => card.wins > 0)
.map(card => Math.pow(2, card.wins - 1))
.reduce((a, b) => a + b, 0);
}
function partB(cards: Card[]): number {
const queue = Array.from(Array(cards.length).keys());
let visited = 0;
while (queue.length > 0) {
const i = queue.pop()!;
visited++;
const card = cards[i];
if (card.wins === 0) continue;
for (let j = 0; j < card.wins; j++) {
queue.push(j + i + 1);
}
}
return visited;
}
function readFile(filename: string): string {
try {
return readFileSync(filename, 'utf-8');
} catch (error) {
throw new Error(`Failed to read file '${filename}': ${error}`);
}
}
function parse(input: string): Card[] {
return input.split('\n').map(line => {
const [winning, scratch] = line.split(': ')[1].split(' | ').map(parseNumbers);
const wins = scratch.filter(x => winning.includes(x)).length;
return new Card(wins);
});
}
function parseNumbers(input: string): number[] {
return input.split(' ').map(Number);
}
class Card {
constructor(public wins: number) {}
}
main();