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

#include <bits/stdc++.h>
using namespace std;
int n, m, i, size[12000], b[12000], a[12000], num, fa[12000], j;
int get(int x) { return fa[x] == x ? x : (fa[x] = get(fa[x])); }
int main() {
  scanf("%d%d", &n, &m);
  for (i = 1; i <= n; ++i) fa[i] = i;
  for (i = 1; i <= n; ++i) {
    scanf("%d", &a[i]);
    if (a[i]) fa[i] = a[i];
  }
  for (i = 1; i <= n; ++i) size[get(i)]++;
  b[0] = 1;
  for (i = 1; i <= n; ++i)
    if (get(i) == i && get(m) != get(i))
      for (j = n - size[i]; j >= 0; --j) b[j + size[i]] |= b[j];
  for (i = m; i; i = a[i]) num++;
  for (i = 0; i <= n; ++i)
    if (b[i]) printf("%d\n", i + num);
}
