#include <bits/stdc++.h>
typedef long long ll;
using namespace std;
const int N = 1e3 + 3;
vector<int>adj[N];
bool marked[N];
int sub[N],D;
int lol=0,sz;
int dfs_subtree(int node, int prev, int mxD){
sub[node] = 1;
for(int child : adj[node]){
if(child != prev && !marked[child]){
sub[node] += dfs_subtree(child, node,mxD+1);
}
}
return sub[node];
}
int find_centroid(int node, int prev){
for(int child : adj[node]){
if(child != prev && !marked[child] && 2 * sub[child] > sz){
return find_centroid(child, node);
}
}
return node;
}
int main()
{
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n;
cin>>n>>D;
for(int i = 1; i < n; i++){
int x;
cin>>x;
adj[x].push_back(i);
adj[i].push_back(x);
}
cout<<(n+D-1)/D;
return 0;
}
