41 lines
866 B
JavaScript
41 lines
866 B
JavaScript
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import fs from "fs";
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/**
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* Main function for Puzzle B
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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 joltages = 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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.reverse();
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const maxVal = joltages[0] + 3;
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joltages.push(0);
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joltages.unshift(maxVal);
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const poss = {};
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const len = [];
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len[maxVal] = 1;
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joltages.forEach((joltage) => {
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poss[joltage] = joltages.filter(
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(val) => val > joltage && val <= joltage + 3
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);
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if (joltage !== maxVal) {
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len[joltage] = 0;
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for (let i = 0; i < poss[joltage].length; i++) {
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len[joltage] += len[poss[joltage][i]];
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}
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}
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});
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return len[0];
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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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