part1.ts

import * as fs from 'fs';
const input = fs.readFileSync('input', 'utf8').split('\n');

let result = 0;

const cache = {};

function trimStart(str) {
	return str.startsWith('.')
		? str
				.split(/(?<=\.)(?=[^.])/)
				.slice(1)
				.join('')
		: str;
}

function findCombinations(row, groups) {
	const line = row + ' ' + groups.join(',');
	if (cache[line]) {
		return cache[line];
	}
	if (groups.length <= 0) {
		return Number(!row.includes('#'));
	}
	if (row.length - groups.reduce((a, b) => a + b) - groups.length + 1 < 0) {
		return 0;
	}

	const firstGroup = groups[0];
	const isFirstGroupDamagedOrUnknown = !row.slice(0, groups[0]).includes('.');
	if (row.length === firstGroup) {
		return Number(isFirstGroupDamagedOrUnknown);
	}

	return (cache[line] ??=
		(row[0] != '#' ? findCombinations(trimStart(row.slice(1)), groups) : 0) +
		(isFirstGroupDamagedOrUnknown && row[firstGroup] != '#'
			? findCombinations(trimStart(row.slice(firstGroup + 1)), groups.slice(1))
			: 0));
}

for (const line of input) {
	const [row, groups] = line
		.split(' ')
		.map((x, i) => (i == 1 ? x.split(',').map((y) => Number(y)) : x));
	result += findCombinations(row, groups);
}

console.log(result);