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;
int a[1005];
bool used[1005];
int b[1005];
int kol, kol2;
vector<int> v[1005];
void dfs(int x) {
  used[x] = true;
  ++kol2;
  for (int i = 0; i < v[x].size(); ++i) {
    int to = v[x][i];
    if (used[to] == false) dfs(to);
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m;
  for (int i = 1; i <= n; ++i) {
    cin >> a[i];
    if (a[i]) {
      v[i].push_back(a[i]);
      v[a[i]].push_back(i);
    }
  }
  int kol = 0;
  int z = m;
  while (z) {
    ++kol;
    z = a[z];
  }
  int kol3 = kol;
  kol = 0;
  dfs(m);
  for (int i = 1; i <= n; ++i)
    if (used[i] == false) {
      kol2 = 0;
      dfs(i);
      b[++kol] = kol2;
    }
  for (int i = 0; i <= n; ++i) used[i] = false;
  used[0] = true;
  for (int i = 1; i <= kol; ++i) {
    for (int j = n; j >= b[i]; --j)
      if (used[j - b[i]]) used[j] = true;
  }
  for (int i = 0; i <= n; ++i)
    if (used[i]) cout << i + kol3 << '\n';
}
