#include <iostream>
#include <algorithm>
#include <cstring>
using namespace std;
const int N = 200010;
int h[N],ne[N],e[N],idx;
int f[N];
int n,m;
void add(int a,int b)
{
    e[idx] = b,ne[idx] = h[a],h[a] = idx++;
}
int dp(int u,int fa)
{
    f[u] = 0;
    int cnt = 0,res = 0;
    for(int i = h[u];i != -1;i = ne[i]){
        int j = e[i];
        if(j == fa) continue;
        cnt++;
        res = max(res,dp(j,u));
        //cout<<j<<" "<<f[j]<<endl;
    }
    return f[u] = res + cnt;
}
int main()
{
    memset(h,-1,sizeof h);
    cin>>n;
    for(int i = 2;i <= n;i++){
        int b;
        cin>>b;
        add(b,i),add(i,b);
    }
    cout<<dp(1,-1)<<endl;
    return 0;
}