#include<algorithm>

 #include<iostream>

 #include<cstdlib>

 #include<cstring>

 #include<cstdio>

 #include<cmath>

 using namespace std;

 #define N 500010

 #define M 20

 int dep[N<<],f[M][N<<];

 int n;

 int q,k;

 int v=,m=;

 int main()

 {

     dep[]=dep[]=dep[]=;

     n=;

     scanf("%d",&q);

     while (q--)

     {

         scanf("%d",&k);

         k--;

         f[][n]=f[][n+]=k;

         dep[n]=dep[n+]=dep[k]+;

         for (int i=;i<M && f[i-][f[i-][n]];i++)

             f[i][n]=f[i][n+]=f[i-][f[i-][n]];

         if (dep[n]>dep[v])

             v=n,++m;

         else if (dep[n]+dep[v]>m)

         {

             int x=v,y=n;

             for (int i=;i<M && dep[x]!=dep[y];i++)

                 if ((dep[x]-dep[y]) & (<<i))

                     x=f[i][x];

             for (int i=M-;i>=;i--)

                 if (f[i][x]!=f[i][y])

                     x=f[i][x],y=f[i][y];

             if (dep[n]+dep[v]-(dep[f[][x]]<<)>m)

                 ++m;

         }

         n+=;

         printf("%d\n",m);

     }

     return ;

 }