52 lines
1.2 KiB
JavaScript
52 lines
1.2 KiB
JavaScript
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import fs from "fs";
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/**
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* Main function for Puzzle A
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*
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* @param {string} data - Puzzle input as a single string.
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* @returns {Promise<number>} Manhattan distance of final position to starting position.
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*/
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async function main(data) {
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const orders = data
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.split(/\r?\n/)
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.map((line) => [line[0], parseInt(line.substring(1))]);
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let facing = 90;
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let position = [0, 0];
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for (const order of orders) {
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switch (order[0]) {
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case "R":
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facing = (facing + 360 + order[1]) % 360;
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break;
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case "L":
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facing = (facing + 360 - order[1]) % 360;
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break;
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case "F":
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const radians = (facing * Math.PI) / 180;
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position[0] += Math.sin(radians) * order[1];
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position[1] += Math.cos(radians) * order[1];
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break;
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case "N":
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position[1] += order[1];
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break;
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case "E":
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position[0] += order[1];
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break;
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case "S":
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position[1] -= order[1];
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break;
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case "W":
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position[0] -= order[1];
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break;
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}
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}
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return Math.abs(position[0]) + Math.abs(position[1]);
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}
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fs.readFile("input", (err, data) => {
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if (err) throw err;
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main(data.toString()).then(console.log).catch(console.error);
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});
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