#include <bits/stdc++.h>
using namespace std;
#define int long long
#define OYY LLONG_MAX
#define faster ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
#define fi first
#define se second
#define FOR for(int i=1;i<=n;i++)
#define mid (start+end)/2
#define pb push_back
#define lim 1505
typedef long long lo;
int n,d;
vector<int> v[lim];
int dist[lim][lim];
vector<int> son;
int dp[lim];
inline void dfs(int node,int ata,int kim,int cur_dist){
//cout<<node<<" "<<kim<<" "<<cur_dist<<endl;
dist[kim][node]=cur_dist;
for(auto go:v[node]){
if(go==ata)continue;
dfs(go,node,kim,cur_dist+1);
}
}
inline void dfs2(int node,int ata){
dp[node]=1;
for(auto go:v[node]){
if(go==ata)continue;
dfs2(go,node);
}
for(auto a:son){
//cout<<node<<" "<<a<<" "<<dist[node][a]<<" "<<dp[node]<<" "<<dp[a]<<endl;
if(dist[node][a]<d)continue;
dp[node]=max(dp[node],dp[a]+1);
}
son.pb(node);
}
int32_t main(){
faster
cin>>n>>d;
FOR{
if(i==1)continue;
int x;cin>>x;
x++;
v[x].pb(i);
v[i].pb(x);
}
FOR{
dfs(i,-1,i,0);
}
dfs2(1,-1);
int cev=0;
FOR{
//cout<<dp[i]<<endl;
cev=max(cev,dp[i]);
}
cout<<cev<<'\n';
return 0;
}
