#include <iostream>
#include <cmath>
#include <unordered_map>
#include <map>
#include <set>
#include <queue>
#include <vector>
#include <string>
#include <iomanip>
#include <algorithm>
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
using namespace std;
typedef long long ll;
ll linf = 1e15+1;
inline void scoobydoobydoo(){
ios::sync_with_stdio(false);
ios_base::sync_with_stdio(false);
cin.tie(NULL); cout.tie(NULL);
}
const int MAXN = 2e5+1;
ll depth[MAXN];
multiset<ll> ms[MAXN];
vector<int> adj[MAXN];
int D, n;
ll ans = -1;
void buildTree(int node, int parent, int w){
depth[node] = w;
for (auto& e : adj[node]){
if (e != parent)buildTree(e, node, w+1);
}
}
void smallerToLarger(int node, int parent){
ms[node].insert(depth[node]);
for (auto& e : adj[node]){
if (e != parent){
smallerToLarger(e, node);
//BRO 'TIS INHERENTLI STL :(
//cout << "start " << node << " " << e << endl;
while (true){
//BOTH EXIST
if (ms[e].empty() || ms[node].empty())break;
//cout << 1 << endl;
if (*ms[e].begin()+*ms[node].begin()-2*depth[node] >= D)break;
//cout << 2 << endl;
//VALID
//PRESERVE SMALLEST DEPTH? LEAST INTERFERABLE?????? Nop, preserve largest???
//^^tis work (?) I not know
//cout << "nodes: " << *ms[e].begin() << " " << *ms[node].begin() << endl;
if (*ms[e].begin() > *ms[node].begin())ms[node].erase(ms[node].begin());
else ms[e].erase(ms[e].begin());
//cout << ms[e].size() << " " << ms[node].size() << endl;
}
//Add all ?
for (auto& x : ms[e]){
ms[node].insert(x);
}
ms[e].clear();
}
}
ans = max(ans, (ll)ms[node].size());
}
int main(){
scoobydoobydoo();
cin >> n >> D;
for (int i = 1; i < n; i++){
int a; cin >> a;
adj[a].push_back(i);
adj[i].push_back(a);
}
buildTree(0, 0, 0);
smallerToLarger(0, 0);
cout << ans << endl;
return 0;
}
