Submission #1269599

#	Time	Username	Problem	Language	Result	Execution time	Memory
1269599		elotelo966	Cat in a tree (BOI17_catinatree)	C++20	0 / 100	1 ms	328 KiB

catinatree

#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;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 40
• Subtask 3: 0 / 49