Submission #1074013

#	Time	Username	Problem	Language	Result	Execution time	Memory
1074013		Malix	Friend (IOI14_friend)	C++14	46 / 100	106 ms	65536 KiB

friend

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

#define REP(a,b,c) for(int a=b;a<c;a++)
#define F first
#define S second
#define PB push_back

typedef long long ll;
typedef vector<int> vi;
typedef vector<vi> vii;
typedef pair<int,int> pi;

vii a;
int n;
vi prt,hst,c,p;
vii dp;

int brute(int confidence[]){
	int m=pow(2,n);
	int ans=0;
	REP(i,0,n)sort(a[i].begin(),a[i].end());
	REP(i,1,m){
		int k=0;
		set<int> st;
		REP(j,0,n){
			if(i&(1<<j))st.insert(j);
		}
		bool flag=1;
		for(auto u:st){
			for(auto v:a[u]){
				if(st.count(v)!=0)flag=0;
			}
		}
		for(auto u:st)k+=confidence[u];
		if(flag)ans=max(ans,k);
	}
	return ans;
}

void solve(int x){
	int mx=0,mx2=0;
	for(auto u:a[x])if(p[x]!=u){
		p[u]=x;
		solve(u);
		mx+=max(dp[u][0],dp[u][1]);
		mx2+=dp[u][0];
	}
	dp[x][1]+=mx2;
	dp[x][0]+=mx;
}

// Find out best sample
int findSample(int N,int confidence[],int host[],int protocol[]){
	n=N;
	prt.resize(n);hst.resize(n);c.resize(n);
	REP(i,1,n)hst[i]=host[i];
	REP(i,1,n)prt[i]=protocol[i];
	REP(i,0,n)c[i]=confidence[i];
	bool flag=1,flag2=1,flag3=1;
	REP(i,1,n)if(prt[i]!=2)flag=0;
	REP(i,1,n)if(prt[i]!=1)flag2=0;
	REP(i,1,n)if(prt[i]!=0)flag3=0;
	if(flag)return *max_element(confidence,confidence+n);
	int sm=0;
	REP(i,0,n)sm+=c[i];
	if(flag2)return sm;
	a.resize(n);
	REP(i,1,n){
		int pos=host[i];
		if(protocol[i]==0||protocol[i]==2){
			a[pos].PB(i);
			a[i].PB(pos);
		}
		if(protocol[i]==1||protocol[i]==2){
			for(auto u:a[pos])if(u!=i){
				a[u].PB(i);
				a[i].PB(u);
			}
		}
	}
	if(n<=10)return brute(confidence);
	if(flag3){
		p.resize(n,-1);dp.resize(n,vi(2));
		REP(i,0,n)dp[i][1]=c[i];
		REP(i,0,n)dp[i][0]=0;
		solve(0);
		return max(dp[0][0],dp[0][1]);
	}
	vi t(n,-1);
	int k=0;
	REP(i,0,n){
		if(t[i]!=-1)continue;
		queue<int> pq;
		pq.push(i);
		t[i]=k;
		while(!pq.empty()){
			int x=pq.front();
			pq.pop();
			for(auto u:a[x])if(t[u]==-1){
				t[u]=k;
				if(t[x]==k)t[u]++;
				pq.push(u);
			}
		}
		k+=2;
	}
	int ans=0;
	REP(i,0,k){
		int sm=0,sm2=0;
		REP(j,0,n)if(t[j]==i)sm+=c[j];
		REP(j,0,n)if(t[j]==i+1)sm2+=c[j];
		ans+=max(sm,sm2);
		i++;
	}
	return ans;
}

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