18 lines
557 B
JavaScript
18 lines
557 B
JavaScript
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const fs = require('fs');
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const data = fs.readFileSync('input.txt', 'utf-8');
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const lines = data.split('\n').map(num => parseInt(num)).sort((a,b)=>(a-b));
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lines.unshift(0); // add the outlet with joltage 0
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lines.push(lines[lines.length-1]+3); // your device has a joltage 3 above the highest
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let threes = 0; // keep track of differences for puzzle solution
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let ones = 0;
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for (let i = 1; i < lines.length; i++) {
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switch (lines[i]-lines[i-1]) {
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case 3:
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threes++;
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break;
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case 1:
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ones++;
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break;
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}
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}
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console.log(ones * threes)
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