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