Submission #422207

#	Time	Username	Problem	Language	Result	Execution time	Memory
422207		dreezy	Friend (IOI14_friend)	C++17	19 / 100	2 ms	460 KiB

friend

#include <bits/stdc++.h>
#include "friend.h"
using namespace std;


/*******************/
// Find out best sample
#define pi pair<int,int>
#define ll long long
#define f first
#define s second
#define pb push_back

vector<vector<int>> dp;
vector<vector<int>> graph;
vector<int> conf;

ll calcdp(int n, int p, bool can){
	if(dp[n][can] != -1) return dp[n][can];
	
	int posans = 0;
	if(can){
		for(int adj : graph[n]){
			if(adj == p) continue;
			posans +=calcdp(adj, n, false);	
		}
	
		dp[n][can] = posans + conf[n] ;
	}
	
	
	posans = 0;
	for(int adj : graph[n]){
		if(adj == p) continue;
		posans+=calcdp(adj, n, true);
	}
	//cout << p<<"->"<<n<<": "<<posans<<", "<<dp[n][can]<<endl;
	dp[n][can] = max(posans, dp[n][can]);
	
	return dp[n][can];
}

int findSample(int n,int confidence[],int host[],int protocol[]){
	dp.clear();
	graph.clear();
	conf.clear();
	conf.assign(n, 0);
	dp.assign(n, vector<int>(2, -1));
	graph.assign(n, vector<int>());
	
	for(int i =0; i<n; i++){
		conf[i] = confidence[i];
	}
	for(int i =1; i<n; i++){
		graph[host[i]].pb(i);
		graph[i].pb(host[i]);
	}
	
	
	calcdp(0, -1, 1);
	return dp[0][1];
}

/*******************/

• Subtask 1: 0 / 11
• Subtask 2: 0 / 8
• Subtask 3: 0 / 8
• Subtask 4: 19 / 19
• Subtask 5: 0 / 23
• Subtask 6: 0 / 31