37 lines
944 B
JavaScript
37 lines
944 B
JavaScript
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const readline = require('readline');
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const fs = require('fs');
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function calculate_score(input) {
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if ('a' <= input && input <= 'z') {
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return input.charCodeAt(0) - 'a'.charCodeAt(0) + 1;
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} else if ('A' <= input && input <= 'Z') {
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return input.charCodeAt(0) - 'A'.charCodeAt(0) + 27;
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} else {
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throw `Invalid character '${input}'`
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}
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}
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async function puzzle() {
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const lines = readline.createInterface({
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input: fs.createReadStream('day3.input'),
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});
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var score = 0;
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for await (const line of lines) {
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const mid = line.length / 2;
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const first = line.substring(0, mid);
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const second = new Set(line.substring(mid));
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for (const character of first) {
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if (second.has(character)) {
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score += calculate_score(character);
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break;
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}
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}
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}
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console.log(`Part 1: Score ${score}`);
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}
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puzzle();
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