64 lines
1.6 KiB
JavaScript
64 lines
1.6 KiB
JavaScript
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import * as fs from "fs";
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function load(filename) {
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return fs.readFileSync(filename, "utf8")
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.trim()
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.split("\n");
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}
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let example = load("example");
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let input = load("input");
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function countSides(x, y, z, input) {
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let count = 0;
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if (input.includes([x+1, y, z].join(","))) count++;
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if (input.includes([x-1, y, z].join(","))) count++;
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if (input.includes([x, y+1, z].join(","))) count++;
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if (input.includes([x, y-1, z].join(","))) count++;
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if (input.includes([x, y, z+1].join(","))) count++;
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if (input.includes([x, y, z-1].join(","))) count++;
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return count;
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}
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function solve(input) {
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// compute the boundaries of the playing field
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let min = Infinity;
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let max = -Infinity;
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input.forEach(line => {
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let [x, y, z] = line.split(",").map(n => parseInt(n));
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min = Math.min(min, x, y, z);
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max = Math.max(max, x, y, z);
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})
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min -=1;
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max +=1;
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// start with an edge and fill up the space
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let count = 0;
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let queue = [[min, min, min]];
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let visited = new Set();
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while (queue.length > 0) {
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const elt = queue.shift();
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const eltstr = elt.join(",");
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const [x, y, z] = elt;
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if (x < min || x > max || y < min || y > max || z < min || z > max) continue;
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if (visited.has(eltstr)) continue
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if (input.includes(eltstr)) continue;
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visited.add(eltstr);
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count += countSides(x, y, z, input);
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queue.push([x+1, y, z]);
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queue.push([x-1, y, z]);
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queue.push([x, y+1, z]);
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queue.push([x, y-1, z]);
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queue.push([x, y, z+1]);
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queue.push([x, y, z-1]);
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}
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return count;
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}
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const exampleOutput = solve(example);
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if (exampleOutput !== 58) {
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console.log("Example failed with " + exampleOutput);
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process.exit(1); // eslint-disable-line
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}
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console.log(solve(input));
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