aoc21-22.ts

import { List, Map, Set } from "immutable";
import { Advent, int, arr } from "advent";

const { compute, computeCheck } = await Advent({ day: 22 });

interface Cube {
	x1: number;
	y1: number;
	z1: number;
	x2: number;
	y2: number;
	z2: number;
}

compute(async (input) => {
	// const data = input.tokens(/,/).map(int);
	const data = input.lines();

	let cubes: Cube[] = [];

	for (let line of data) {
		let [op, pos] = line.split(" ");
		let [xr, yr, zr] = pos.split(",");
		let [x1, x2] = xr.split("=")[1].split("..").map(int);
		let [y1, y2] = yr.split("=")[1].split("..").map(int);
		let [z1, z2] = zr.split("=")[1].split("..").map(int);
		let cur = { x1, y1, z1, x2: x2+1, y2: y2+1, z2: z2+1 };

		cubes = cubes.flatMap((c) => sub(c, cur));

		if (op === "on") {
			cubes.push(cur);
		}
	}

	return cubes.map((c) => vol(c)).reduce((a, b) => a + b, 0n).toString();
}, 2);

function vol(c: Cube) {
	return BigInt(c.x2 - c.x1) * BigInt(c.y2 - c.y1) * BigInt(c.z2 - c.z1);
}

function sub(a: Cube, b: Cube): Cube[] {
	if (contains(b, a)) {
		return [];
	}

	if (!intersects(a, b)) {
		return [a];
	}

	let xSplits = [b.x1, b.x2].filter((x) => a.x1 < x && x < a.x2);
	let ySplits = [b.y1, b.y2].filter((y) => a.y1 < y && y < a.y2);
	let zSplits = [b.z1, b.z2].filter((z) => a.z1 < z && z < a.z2);

	let xv = [a.x1, ...xSplits, a.x2];
	let yv = [a.y1, ...ySplits, a.y2];
	let zv = [a.z1, ...zSplits, a.z2];

	let res: Cube[] = [];

	for (let i = 0; i < xv.length - 1; i++) {
		for (let j = 0; j < yv.length - 1; j++) {
			for (let k = 0; k < zv.length - 1; k++) {
				res.push({
					x1: xv[i],
					y1: yv[j],
					z1: zv[k],
					x2: xv[i+1],
					y2: yv[j+1],
					z2: zv[k+1],
				});
			}
		}
	}

	return res.filter((c) => !contains(b, c));
}

function contains(a: Cube, b: Cube): boolean {
	return a.x1 <= b.x1 && a.x2 >= b.x2 && a.y1 <= b.y1 && a.y2 >= b.y2 && a.z1 <= b.z1 && a.z2 >= b.z2;
}

function intersects(a: Cube, b: Cube): boolean {
	return a.x1 <= b.x2 && a.x2 >= b.x1 && a.y1 <= b.y2 && a.y2 >= b.y1 && a.z1 <= b.z2 && a.z2 >= b.z1;
}