33 lines
644 B
JavaScript
33 lines
644 B
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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*/
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async function main(data) {
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const adapters = data
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.split(/\r?\n/)
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.map((line) => parseInt(line))
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.sort((a, b) => a - b);
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/** @type {number[]} */
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const diffs = [];
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let curNum = 0;
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while (adapters.length > 0) {
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const delta = adapters[0] - curNum;
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diffs[delta] = (diffs[delta] ?? 0) + 1;
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curNum = adapters.shift();
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}
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return diffs[1] * (diffs[3] + 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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