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>
int x, p;
int a[1000];
int b[1000];
int d[1000];
int dp[1000];
int dfs(int y) {
  if (y == x) return -1e9;
  if (a[y] == 0) return 1;
  return dfs(a[y] - 1) + 1;
}
int dfs2(int y) {
  if (y == x) {
    if (a[y] == 0) {
      p = 1;
    } else {
      p = dfs2(a[y] - 1) + 1;
    }
    return p;
  }
  if (a[y] == 0) return 1;
  return dfs2(a[y] - 1) + 1;
}
int main() {
  int n, c = 0, i, j;
  scanf("%d %d", &n, &x);
  x--;
  for (i = 0; i < n; i++) {
    scanf("%d", &a[i]);
    if (a[i] != 0) d[a[i] - 1] = 1;
  }
  for (i = 0; i < n; i++) {
    if (d[i] == 0) {
      int y = dfs(i);
      if (y >= 0) {
        b[c++] = y;
      } else {
        dfs2(i);
      }
    }
  }
  dp[0] = 1;
  for (i = 0; i < c; i++) {
    for (j = n - 1; j >= 0; j--) {
      if (dp[j] == 0) continue;
      dp[j + b[i]] = 1;
    }
  }
  for (i = 0; i < n; i++) {
    if (dp[i] == 1) printf("%d\n", i + p);
  }
  return 0;
}
