Submission #43856194

---

Source Code Expand

import java.util.ArrayList;
import java.util.Deque;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.List;
import java.util.Scanner;
import java.util.Set;

public class Main {
	public static void main(String[] args) throws Exception {
		try (Scanner scanner = new Scanner(System.in)) {
			int n = scanner.nextInt();
			List<Integer> list = new ArrayList<>();
			for (int i = 0; i < n; i++) {
				list.add(scanner.nextInt());
			}

			Deque<Integer> deque = new LinkedList<>();
			Set<Integer> path = new HashSet<>();
			int seq = 1;
			while (!path.contains(seq)) {
				deque.addLast(seq);
				path.add(seq);
				seq = list.get(seq - 1);
			}

			List<Integer> result = new ArrayList<>();
			result.add(seq);
			int last = deque.removeLast();
			while (last != seq) {
				result.add(last);
				last = deque.removeLast();
			}

			System.out.println(result.size());
			for (int i = result.size() - 1; i >= 0; i--) {
				System.out.print(result.get(i) + " ");
			}
		}
	}
}

Submission Info

Judge Result