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;
const int N = 1e3 + 5;
int n, m, a[N], cur, b[N];
bool used[N];
void dfs(int v) {
  cur++;
  if (a[v]) {
    dfs(a[v]);
  }
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
    if (a[i]) {
      b[a[i]] = i;
    }
  }
  bitset<N> dp;
  dfs(m);
  dp[cur] = true;
  int z = m;
  while (z > 0) {
    int x = b[z];
    b[z] = N;
    z = x;
  }
  for (int i = 1; i <= n; i++) {
    if (!b[i]) {
      cur = 0;
      dfs(i);
      dp |= (dp << cur);
    }
  }
  for (int i = 1; i < N; i++) {
    if (dp[i]) {
      cout << i << "\n";
    }
  }
}
