77 lines
1.8 KiB
JavaScript
77 lines
1.8 KiB
JavaScript
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const fs = require('fs');
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const inputArray = fs.readFileSync('input.txt').toString().split("\n");
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// Part One
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const lines = inputArray.length;
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const oneCount = [];
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for (i in inputArray[0]) {
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oneCount[i] = 0;
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}
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const gammaArray = Object.assign([], oneCount);
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const epsilonArray = Object.assign([], oneCount);
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for(i in inputArray) {
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const line = inputArray[i];
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for (x in line) {
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if (line[x] === "1") {
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oneCount[x]++;
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}
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}
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}
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for (i in oneCount) {
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if (oneCount[i] > (lines / 2)) {
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gammaArray[i] = 1;
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} else {
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epsilonArray[i] = 1;
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}
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}
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const gamma = parseInt(gammaArray.join(""), 2);
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const epsilon = parseInt(epsilonArray.join(""), 2);
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console.log(`${gamma} * ${epsilon} = ${gamma * epsilon}`);
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// Part Two
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function arrayFilter(unfilteredArray, testChar, rating) {
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if (unfilteredArray.length === 1) {
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return unfilteredArray;
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}
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let count = 0;
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let greatest = "0";
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const lines = unfilteredArray.length;
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for(i in unfilteredArray) {
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count = count + parseInt(unfilteredArray[i][testChar]);
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}
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if (count >= (lines / 2)) {
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greatest = "1";
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}
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if (rating === "oxygen") {
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filteredArray = unfilteredArray.filter(line => line[testChar] === greatest)
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} else {
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filteredArray = unfilteredArray.filter(line => line[testChar] !== greatest)
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}
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return filteredArray;
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}
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let oxygenRatingArray = Object.assign([], inputArray);
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let co2RatingArray = Object.assign([], inputArray);
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for (x in oxygenRatingArray[0]) {
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oxygenRatingArray = arrayFilter(oxygenRatingArray, x, "oxygen")
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}
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for (x in co2RatingArray[0]) {
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co2RatingArray = arrayFilter(co2RatingArray, x, "co2")
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}
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const oxygen = parseInt(oxygenRatingArray.join(""), 2);
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const co2 = parseInt(co2RatingArray.join(""), 2);
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console.log(`${oxygen} * ${co2} = ${oxygen * co2}`);
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