#include<iostream> #include<vector> #include<algorithm> using namespace std; const int MAX_N=2e5+5; int n,D; vector<int>g[MAX_N]; vector<int>dp[MAX_N]; int height[MAX_N]; void merge(int u,int v) { vector<int>tmp; tmp.resize(dp[v].size()); for(int curdepth=0;curdepth<dp[v].size();curdepth++) { int curbest=0; int curval=dp[v][dp[v].size()-1-curdepth]; int otherdepth=max(curdepth+1,D-curdepth-1); if(otherdepth<dp[u].size()) { curval+=dp[u][dp[u].size()-1-otherdepth]; curbest=max(curbest,curval); } //case 1 curval=0; if(dp[u].size()>(curdepth+1))curval=dp[u][dp[u].size()-1-(curdepth+1)]; otherdepth=max(curdepth,D-(curdepth+1)-1); if(curval!=0 && otherdepth<dp[v].size()) { curval+=dp[v][dp[v].size()-1-otherdepth]; curbest=max(curbest,curval); } //case 2 tmp.push_back(curbest); } for(int newdepth=dp[v].size();newdepth>=1;newdepth--) { int curval=tmp[newdepth-1]; int pos=dp[u].size()-1-newdepth; dp[u][pos]=max(dp[u][pos],curval); if(pos)dp[u][pos]=max(dp[u][pos],dp[u][pos-1]); } //vector<int>().swap(dp[v]); } void initdfs(int u,int par) { height[u]=1; for(int v:g[u]) { if(v==par)continue; initdfs(v,u); height[u]=max(height[u],height[v]+1); } } void dfs(int u,int par) { int mx=-1,bigchild=-1; for(int v:g[u]) { if(v==par)continue; if(height[v]>mx) { mx=height[v]; bigchild=v; } } if(bigchild==-1) { dp[u].push_back(1); return; } dfs(bigchild,u); swap(dp[bigchild],dp[u]); //vector<int>().swap(dp[bigchild]); int d1=0; if(dp[u].size()>D-1)d1=dp[u][dp[u].size()-1-(D-1)]; dp[u].push_back(d1+1); int zerocase=0; for(int v:g[u]) { if(v==par or v==bigchild)continue; dfs(v,u); if(dp[v].size()>D-1) { zerocase+=dp[v][dp[v].size()-1-(D-1)]; } merge(u,v); } dp[u].back()+=zerocase; dp[u].back()=max(dp[u][dp[u].size()-2],dp[u].back()); } int main () { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cin>>n>>D; for(int i=1;i<n;i++) { int x; cin>>x; g[x].push_back(i); g[i].push_back(x); } initdfs(0,-1); dfs(0,-1); cout<<dp[0].back()<<"\n"; return 0; }