39 lines
1 KiB
JavaScript
39 lines
1 KiB
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');
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let max = 0
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// who really needs semicolons anyway
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for (let i = 0; i < lines.length; i++) {
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let line = lines[i]
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let rowCode = line.substring(0, 7).replace(/F/g, "0").replace(/B/g, "1")
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let colCode = line.substring(7).replace(/L/g, "0").replace(/R/g, "1")
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// another excuse to flex that recursive muscle
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function getIndexFromBSP (BSP, min, max) {
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if (BSP.length != 1) {
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[min, max] = getIndexFromBSP (BSP.substring(0, BSP.length-1), min, max)
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}
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switch (BSP[BSP.length-1]) {
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case '0':
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max = Math.floor((min + max) / 2)
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break
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case '1':
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min = Math.ceil((min + max) / 2)
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break
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default:
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console.log("something went wrong")
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}
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return [min, max]
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}
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let row = getIndexFromBSP(rowCode, 0, 127)[0]
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let col = getIndexFromBSP(colCode, 0, 7)[0]
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let seatID = (row * 8) + col
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max = seatID > max ? seatID : max
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}
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console.log(max)
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