97 lines
3.0 KiB
JavaScript
97 lines
3.0 KiB
JavaScript
const fs = require('fs');
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const path = require('path');
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function parseSchematic(filePath) {
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try {
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const data = fs.readFileSync(filePath, 'utf8');
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return data.split('\n').map(line => line.trim());
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} catch (err) {
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throw new Error(`Error reading file: ${filePath}, ${err.message}`);
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}
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}
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function getAdjacentPositions(rows, cols, row, col) {
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const positions = [];
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for (let i = Math.max(0, row - 1); i <= Math.min(rows - 1, row + 1); i++) {
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for (let j = Math.max(0, col - 1); j <= Math.min(cols - 1, col + 1); j++) {
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if (i !== row || j !== col) {
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positions.push([i, j]);
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}
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}
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}
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return positions;
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}
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function findStartOfNumber(schematic, row, col) {
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while (col > 0 && /\d/.test(schematic[row][col - 1])) {
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col--;
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}
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return col;
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}
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function extractFullNumber(schematic, startRow, startCol) {
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startCol = findStartOfNumber(schematic, startRow, startCol);
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let number = '';
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let col = startCol;
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while (col < schematic[startRow].length && /\d/.test(schematic[startRow][col])) {
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number += schematic[startRow][col];
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schematic[startRow] = schematic[startRow].substring(0, col) + '.' + schematic[startRow].substring(col + 1);
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col++;
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}
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return parseInt(number, 10);
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}
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function findGearsAndCalculateRatios(schematic) {
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const rows = schematic.length;
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const cols = schematic[0].length;
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let totalRatioSum = 0;
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for (let row = 0; row < rows; row++) {
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for (let col = 0; col < cols; col++) {
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if (schematic[row][col] === '*') {
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const partNumbers = [];
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for (const [i, j] of getAdjacentPositions(rows, cols, row, col)) {
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if (/\d/.test(schematic[i][j])) {
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const partNumber = extractFullNumber(schematic, i, j);
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if (!partNumbers.includes(partNumber)) {
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partNumbers.push(partNumber);
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}
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}
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}
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if (partNumbers.length === 2) {
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const gearRatio = partNumbers[0] * partNumbers[1];
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totalRatioSum += gearRatio;
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console.log(`Found gear at line ${row + 1} with ratio ${gearRatio}`);
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}
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}
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}
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}
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return totalRatioSum;
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}
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function runTest() {
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const testSchematic = parseSchematic(path.join(__dirname, '../test.txt'));
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const testResult = findGearsAndCalculateRatios(testSchematic);
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console.log(`Test Result: ${testResult}`);
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console.assert(testResult === 467835, `Test failed: Expected 467835, got ${testResult}`);
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}
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function main() {
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try {
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runTest();
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console.log("Test passed successfully.");
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const inputSchematic = parseSchematic(path.join(__dirname, '../input.txt'));
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const totalRatioSum = findGearsAndCalculateRatios(inputSchematic);
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console.log(`Total sum of gear ratios: ${totalRatioSum}`);
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} catch (error) {
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console.error(error.message);
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}
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}
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main();
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