#include <bits/stdc++.h>
using namespace std;
template <typename T, typename U>
inline void smin(T &a, const U &b) {
  if (a > b) a = b;
}
template <typename T, typename U>
inline void smax(T &a, const U &b) {
  if (a < b) a = b;
}
template <class T>
inline void gn(T &first) {
  char c, sg = 0;
  while (c = getchar(), (c > '9' || c < '0') && c != '-')
    ;
  for ((c == '-' ? sg = 1, c = getchar() : 0), first = 0; c >= '0' && c <= '9';
       c = getchar())
    first = (first << 1) + (first << 3) + c - '0';
  if (sg) first = -first;
}
template <class T1, class T2>
inline void gn(T1 &x1, T2 &x2) {
  gn(x1), gn(x2);
}
int power(int a, int b, int m, int ans = 1) {
  for (; b; b >>= 1, a = 1LL * a * a % m)
    if (b & 1) ans = 1LL * ans * a % m;
  return ans;
}
int pa[1000100], dp[1000100];
pair<int, int> mx[1000100][2];
int main() {
  int n;
  cin >> n;
  n++;
  for (int i = 2; i <= n; i++) {
    gn(pa[i]);
    int u = i;
    dp[u] = 1;
    while (u) {
      int f = pa[u];
      if (mx[f][0].second == u)
        mx[f][0] = pair<int, int>(dp[u], u);
      else {
        smax(mx[f][1], pair<int, int>(dp[u], u));
        if (mx[f][1].first > mx[f][0].first) swap(mx[f][0], mx[f][1]);
      }
      if (dp[f] == max(mx[f][0].first, mx[f][1].first + 1)) break;
      dp[f] = max(mx[f][0].first, mx[f][1].first + 1);
      u = f;
    }
    printf("%d\n", mx[1][0].first);
  }
  return 0;
}
