20 20
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 10 4
0 1 4 2 7 0 10 0 5 8
 10 7
10 8 6 5 0 0 0 4 3 9
 10 1
8 7 0 2 0 10 0 0 3 5
 10 7
7 9 2 10 0 0 0 3 5 1
 10 2
10 0 9 0 0 4 2 6 8 0
 10 2
0 7 0 10 8 0 4 2 3 0

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
 3
4
8
9
 1
5
6
10
 2
4
5
7
8
10
 1
2
6
7
 1
2
3
4
6
7
8
9
 4
5
6
7
8

import java.util.Scanner;

public class Prob316B {
	public static void main(String[] Args) {
		Scanner scan = new Scanner(System.in);
		int x = scan.nextInt();
		int k = scan.nextInt() - 1;

		int[] uf = new int[x];
		for (int i = 0; i < x; i++)
			uf[i] = i;

		int[] arr = new int[x];
		for (int i = 0; i < x; i++)
			arr[i] = scan.nextInt() - 1;

		for (int i = 0; i < x; i++)
			if (arr[i] != -1)
				merge(uf, i, arr[i]);

		int[] sizes = new int[x];
		for (int i = 0; i < x; i++)
			sizes[getpar(uf, i)]++;

		int index = 1;
		for (int i = 0; i < x; i++)
			while (arr[k] != -1) {
				k = arr[k];
				index++;
			}
		sizes[k] = 0;

		boolean[] dp = new boolean[x];
		dp[0] = true;
		for (int i = 0; i < x; i++)
			if (sizes[i] != 0)
				for (int j = x - 1; j >= sizes[i]; j--)
					if (dp[j - sizes[i]])
						dp[j] = true;

		for (int i = 0; i < x; i++)
			if (dp[i])
				System.out.println(i + index);
	}

	static int getpar(int[] arr, int i) {
		return arr[i] == i ? i : getpar(arr, arr[i]);
	}

	static void merge(int[] arr, int a, int b) {
		arr[getpar(arr, a)] = getpar(arr, b);
	}
}
