Submission #1280900

#	Time	Username	Problem	Language	Result	Execution time	Memory
1280900		Leyna	Friend (IOI14_friend)	C++20	100 / 100	15 ms	2188 KiB

friend

#include "friend.h"
#include <bits/stdc++.h>

using namespace std;

/*
SUBTASK 4

vector<int> take, not_take;
vector<vector<int>> children;

void dfs(int u, int confidence[]){
	take[u] += confidence[u];
	for (int v : children[u]){
		dfs(v, confidence);
		take[u] += not_take[v];
		not_take[u] += max(not_take[v], take[v]);
	}
}

// Find out best sample
int findSample(int n,int confidence[],int host[],int protocol[]){
	children.resize(n);
	for (int i=1; i<n; i++){
		children[host[i]].push_back(i);
	}
	take = not_take = vector<int>(n);
	dfs(0, confidence);
	return max(take[0], not_take[0]);
}*/

/*
SUBTASK 2
int findSample(int n,int confidence[],int host[],int protocol[]){
	int ans = 0;
	for (int i=0; i<n; i++) ans += confidence[i];
	return ans;
}

*/
/*
int findSample(int n,int confidence[],int host[],int protocol[]){
	int ans = 0;
	for (int i=0; i<n; i++) ans = max(confidence[i], ans);
	return ans;
}*/

int findSample(int n,int confidence[],int host[],int protocol[]){
	int res = 0;

	vector<int> p(n), q(n);
	for (int i=0; i<n; i++) p[i] = confidence[i];
	for (int i=n-1; i > 0; i--){
		int j = host[i];
		if (protocol[i] == 0){
			// IAmYourFriend
			p[j] += q[i];
			q[j] += max(p[i], q[i]);
		}
		else if (protocol[i] == 1){
			// MyFriendsAreYourFriends
			p[j] = max(p[j] + p[i], max(p[j] + q[i], q[j] + p[i]));
			q[j] += q[i];
		}
		else{
			p[j] = max(p[j] + q[i], p[i] + q[j]);
			q[j] += q[i];
		}
		/*for (int i=0; i<n; i++){
			cout << p[i] << " " << q[i] << endl;
		}
		cout << "-------" << endl;*/
	}
	res = max(p[0], q[0]);

	/*for (int i=0; i<n; i++){
		cout << p[i] << " " << q[i] << endl;
	}*/

	return res;
}

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