Submission #58629

#	Time	Username	Problem	Language	Result	Execution time	Memory
58629		ngkan146	Friend (IOI14_friend)	C++11	16 / 100	6 ms	3068 KiB

friend

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

#define IAmYourFriend 0
#define MyFriendsAreYourFriends 1
#define WeAreYourFriends 2

#define WHITE 0
#define BLACK 1

int dsup[100000];
int dsu_p(int x){
	return x == dsup[x] ? x : dsup[x] = dsu_p(dsup[x]);
}
void dsu_union(int x,int y){
	dsup[dsu_p(y)] = dsu_p(x);
}

int val[100000], color[100000];
vector <int> G[100000];
vector <int> lst[2];
bool visited[100000];

void dfs(int u){
	visited[u] = 1;
	lst[color[u]].push_back(u);
	if (val[dsu_p(u)] < val[u])
		swap(val[dsu_p(u)], val[u]);
	for(auto v: G[u]){
		if (!visited[v])
			dfs(v);
	}
}
int findSample(int n,int a[],int host[],int type[]){
	for(int i=0;i<n;i++)
		dsup[i] = i,
		val[i] = a[i];
		
	//~ color[0] = WHITE;
	for(int i=1;i<n;i++){
		G[host[i]].push_back(i);
		G[i].push_back(host[i]);
		if (type[i] == IAmYourFriend){
			color[i] = color[host[i]] ^ 1;
		}
		else if (type[i] == MyFriendsAreYourFriends){
			color[i] = color[host[i]];
		}
		else{
			color[i] = color[host[i]];
			dsu_union(i, host[i]);
		}
	}
	
	int answer = 0;
	for(int i=0;i<n;i++){
		if (visited[i])	continue;
		lst[0].clear();
		lst[1].clear();
		dfs(i);
		int res[2] = {0,0};
		for(auto v: lst[0]){
			if (dsu_p(v) == v)	res[0] += val[v];
		}
		for(auto v: lst[1]){
			if (dsu_p(v) == v)	res[1] += val[v];
		}
		answer += max(res[0], res[1]);
	}
	return answer;
}

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