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 n, x, a[1024], b[1024], v[1024] = {1};
int main() {
  scanf("%d%d", &n, &x);
  for (int i = 1; i <= n; ++i) scanf("%d", &a[i]), ++b[a[i]];
  int t = 0;
  for (int i = 1; i <= n; ++i)
    if (!b[i]) {
      int z = 0, f = 0;
      for (int j = i; j > 0; j = a[j], ++z)
        if (f |= j == x) ++t;
      if (!f)
        for (int j = n; j >= z; --j) v[j] |= v[j - z];
    }
  for (int i = 0; i < n; ++i)
    if (v[i]) printf("%d\n", i + t);
  return 0;
}
