Node.js) 백준 9466번: 텀 프로젝트

https://www.acmicpc.net/problem/9466

9466번: 텀 프로젝트

const fs = require('fs');
const input = fs
	.readFileSync('./dev/stdin')
	.toString()
	.trim()
	.split('\n')
	.map((v) => v.split(' ').map(Number));

const [T] = input.shift();
const answer = [];
for (let i = 0; i < T; i++) {
	let [N] = input.shift();
	let term = input.shift().map((v) => v - 1);
	answer.push(calc(N, term));
}
console.log(answer.join('\n'));

function calc(N, term) {
	let visited = new Array(term.length).fill(false);
	for (let i = 0; i < term.length; i++) {
		const stack = [];
		if (!visited[i]) {
			visited[i] = true;
			stack.push(i);
			let next = term[i];
			while (!visited[next]) {
				visited[next] = true;
				stack.push(next);
				next = term[next];
			}
			stack.push(next);
		}
		if (stack.length != new Set(stack).size) {
			const start = stack.pop();
			const notCycle = stack.findIndex((v) => v == start);
			const cnt = stack.length - notCycle;
			N -= cnt;
		}
	}

	return N;
}