제출 #242418

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
242418		joseacaz	친구 (IOI14_friend)	C++17	46 / 100	41 ms	2040 KiB

friend

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

#define pb push_back

using namespace std;
typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;

const int MAXN = 1005;
int prot[3], on[MAXN], DP[MAXN][2], visDP[MAXN][2];
int ans, c[MAXN], vis[MAXN];
vi Graph[MAXN];

int solve(int node, int f, int p = 0)
{
    if(visDP[node][f])
        return DP[node][f];

    int res1 = 0, res2 = 0;
    for(auto i : Graph[node])
    {
        if(i == p)
            continue;
        res1 += solve(i, 1, node);
        res2 += solve(i, 0, node);
    }
    
    visDP[node][f] = 1;
    if(f)
        return DP[node][f] = max(res1, res2 + c[node]);
    else
        return DP[node][f] = res1;
}

// Find out best sample
int findSample(int N, int _conf[], int host[], int protocol[])
{
    if(N > 1000)
        return 0;

    for(int i = 0; i < N; i++)
    {
        c[i] = _conf[i];
        if(i >= 1)
            prot[protocol[i]]++;
    }
    
    //S1
    if(N <= 10)
    {
        for(int i = 1; i < N; i++)
        {
            if(protocol[i] == 0)
            {
                Graph[host[i]].pb(i);
                Graph[i].pb(host[i]);
            }
            else if(protocol[i] == 1)
            {
                for(auto v : Graph[host[i]])
                {
                    Graph[v].pb(i);
                    Graph[i].pb(v);
                }
            }
            else if(protocol[i] == 2)
            {
                for(auto v : Graph[host[i]])
                {
                    Graph[v].pb(i);
                    Graph[i].pb(v);
                }
                Graph[host[i]].pb(i);
                Graph[i].pb(host[i]);
            }
        }
        int aux;
        for(int i = 0; i < (1 << N); i++)
        {
            aux = 0;
            for(int j = 0; j < N; j++)
            {
                on[j] = 0;
                if(i & (1 << j))
                {
                    on[j] = 1;
                    aux += c[j];
                }
            }
            
            bool ind = 1;
            for(int node = 0; node < N; node++)
                if(on[node])
                    for(auto j : Graph[node])
                        if(on[j])
                            ind = 0;
            if(!ind)
                continue;
            ans = max(ans, aux);
        }
    }
    //S2
    else if(prot[1] == N - 1)
    {
        for(int i = 0; i < N; i++)
            ans += c[i];
    }
    //S3
    else if(prot[2] == N - 1)
    {
        for(int i = 0; i < N; i++)
            ans = max(ans, c[i]);
    }
    //S4
    else if(prot[0] == N - 1)
    {
        for(int i = 1; i < N; i++)
        {
            if(protocol[i] == 0)
            {
                Graph[host[i]].pb(i);
                Graph[i].pb(host[i]);
            }
        }
        ans = solve(0, 1);
    }
    //S5
    else if(prot[0] + prot[1] == N - 1)
    {
        for(int i = 1; i < N; i++)
        {
            if(protocol[i] == 0)
            {
                Graph[host[i]].pb(i);
                Graph[i].pb(host[i]);
            }
            else if(protocol[i] == 1)
            {
                for(auto v : Graph[host[i]])
                {
                    Graph[v].pb(i);
                    Graph[i].pb(v);
                }
            }
        }
        
        queue<pii> Q;
        Q.push({0, 0});
        pii aux;
        int nodes[2] = {0, 0};
        while(!Q.empty())
        {
            aux = Q.front();
            Q.pop();
            nodes[aux.second]++;
            for(auto i : Graph[aux.first])
            {
                if(!vis[i])
                {
                    Q.push({i, aux.second^1});
                    vis[i] = 1;
                }
            }
        }
        ans = max(nodes[0], nodes[1]);
    }
    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