#include <bits/stdc++.h>
 
using namespace std;
 
struct Bipartite_Matching
{
  vector< vector< int > > graph;
  vector< int > match, alive, used;
  int timestamp;
 
  Bipartite_Matching(int n)
  {
    timestamp = 0;
    graph.resize(n);
    alive.assign(n, 0);
    used.assign(n, 0);
    match.assign(n, -1);
  }
 
  void add_edge(int u, int v)
  {
    graph[u].push_back(v);
    graph[v].push_back(u);
  }
 
  bool dfs(int v)
  {
    used[v] = timestamp;
    for(int i = 0; i < graph[v].size(); i++) {
      int u = graph[v][i], w = match[u];
      if(alive[u] == 0) continue;
      if(w == -1 || (used[w] != timestamp && dfs(w))) {
        match[v] = u;
        match[u] = v;
        return (true);
      }
    }
    return (false);
  }
 
  int bipartite_matching()
  {
    int ret = 0;
    for(int i = 0; i < graph.size(); i++) {
      if(alive[i] == 0) continue;
      if(match[i] == -1) {
        ++timestamp;
        ret += dfs(i);
      }
    }
    return (ret);
  }
 
  int add(int k)
  {
    alive[k] = 1;
    ++timestamp;
    return (dfs(k));
  }
 
};
 
int main()
{
  int N, A[150000], idx[150000];
  vector< int > g[150000];
  bool dep[150000] = {};
 
  cin >> N;
  ++N;
  for(int i = 1; i < N; i++) {
    cin >> idx[i];
    g[idx[i]].push_back(i);
    dep[i] = dep[idx[i]] ^ 1;
  }
 
  Bipartite_Matching flow(N);
  vector< int > left, right;
  for(int i = 0; i < N; i++) {
    if(dep[i]) left.push_back(i);
    else right.push_back(i);
  }
 
  for(int i = 1; i < N; i++) {
    int oi, beet;
    if(dep[i]) oi = lower_bound(begin(left), end(left), i) - begin(left);
    else oi = (int) (lower_bound(begin(right), end(right), i) - begin(right)) + left.size();
 
    if(dep[idx[i]]) beet = lower_bound(begin(left), end(left), idx[i]) - begin(left);
    else beet = (int) (lower_bound(begin(right), end(right), idx[i]) - begin(right)) + left.size();
 
    flow.add_edge(oi, beet);
  }
  flow.alive[(int) (lower_bound(begin(right), end(right), 0) - begin(right)) + left.size()] = true;
 
  flow.bipartite_matching();
  int ret = 0;
  for(int i = 1; i < N; i++) {
    int oi;
    if(dep[i]) oi = lower_bound(begin(left), end(left), i) - begin(left);
    else oi = (int) (lower_bound(begin(right), end(right), i) - begin(right)) + left.size();
    ret += flow.add(oi);
    cout << ret << endl;
  }
 
 
}