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 = 1005;
int dep[N], fa[N], tot[N];
bool dp[N], vis[N];
int find(int x) {
  if (x == fa[x])
    return x;
  else {
    int f = fa[x];
    tot[f] += tot[x];
    tot[x] = 0;
    fa[x] = find(fa[x]);
    dep[x] = dep[f] + 1;
    return fa[x];
  }
}
void make(int x, int y) {
  int fx = find(x);
  fa[y] = x;
  tot[fx] += tot[y];
  tot[y] = 0;
}
int main() {
  int n, x;
  scanf("%d%d", &n, &x);
  for (int i = 1; i <= n; i++) {
    fa[i] = i;
    dep[i] = 1;
    tot[i] = 1;
  }
  int f;
  for (int i = 1; i <= n; i++) {
    scanf("%d", &f);
    if (f != 0) make(f, i);
  }
  vector<int> a;
  memset(vis, false, sizeof(vis));
  int fx = find(x), s = dep[x];
  vis[fx] = true;
  for (int i = 1; i <= n; i++) {
    int f = find(i);
    if (!vis[f]) {
      vis[f] = true;
      a.push_back(tot[f]);
    }
  }
  memset(dp, false, sizeof(dp));
  dp[0] = true;
  for (int i = 0; i < a.size(); i++) {
    int v = a[i];
    for (int i = n; i >= v; i--) {
      if (dp[i - v]) dp[i] = true;
    }
  }
  for (int i = 0; i + s <= n; i++) {
    if (dp[i]) printf("%d\n", i + s);
  }
  return 0;
}
