Submission #775358

#	Time	Username	Problem	Language	Result	Execution time	Memory
775358		danikoynov	Friend (IOI14_friend)	C++14	46 / 100	21 ms	4844 KiB

friend

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

using namespace std;

// Find out best sample
const int maxn = 1010;
typedef long long ll;

vector < int > adj[maxn];
int edges[maxn][maxn];
void add_edge(int v, int u)
{
    adj[v].push_back(u);
    adj[u].push_back(v);
    edges[v][u] = edges[u][v] = 1;
}

vector < int > ord;

int used[maxn];
void bfs(int v)
{
    queue < int > q;
    used[v] = 1;
    q.push(v);
    while(!q.empty())
    {
        int cur = q.front();
        q.pop();
        ord.push_back(cur);
        for (int u : adj[cur])
        {

            if (used[u] == 0)
            {
                if (used[cur] == 1)
                    used[u] = 2;
                else
                    used[u] = 1;
                q.push(u);
            }
        }
    }
}

int con[maxn], dp[maxn][2];
void dfs(int v, int p)
{
    dp[v][1] = con[v];
    used[v] = 1;
    for (int u : adj[v])
    {
        if (u == p)
            continue;
        dfs(u, v);
        dp[v][0] += max(dp[u][0], dp[u][1]);
        dp[v][1] += dp[u][0];
    }
}
int findSample(int n,int confidence[],int host[],int protocol[])
{
    bool only_my = true, only_we = true;
    for (int i = 1; i < n; i ++)
    {
        if (protocol[i] != 1)
            only_my = false;
        if (protocol[i] != 2)
            only_we = false;
    }
    for (int i = 0; i < n; i ++)
    {
        con[i] = confidence[i];
    }

    if (n <= 10)
    {
        for (int i = 1; i < n; i ++)
        {
            if (protocol[i] == 0)
            {
                add_edge(i, host[i]);
            }
            else if (protocol[i] == 1)
            {
                for (int u : adj[host[i]])
                    add_edge(u, i);
            }
            else
            {
                for (int u : adj[host[i]])
                    add_edge(u, i);
                add_edge(i, host[i]);
            }

        }
        ll ans = 0;
        for (int mask = 0; mask < (1 << n); mask ++)
        {
            bool tf = true;
            for (int bit1 = 0; bit1 < n; bit1 ++)
                for (int bit2 = 0; bit2 < n; bit2 ++)
            {
                if ((mask & (1 << bit1)) > 0 && (mask & (1 << bit2)) > 0)
                {
                    if (edges[bit1][bit2])
                        tf = false;
                }
            }
            ///cout << mask << " : " << tf << endl;
            if (!tf)
                continue;
            ll cur = 0;
            for (int i = 0; i < n; i ++)
                if ((mask & (1 << i)) > 0)
                cur += confidence[i];
            ans = max(ans, cur);
        }
        return ans;

    }
    else if (only_my)
    {

        int ans = 0;
        for (int i = 0; i < n; i ++)
            ans += confidence[i];
        return ans;
    }
    else if (only_we)
    {
        int ans = 0;
        for (int i = 0; i < n; i ++)
            ans = max(ans, confidence[i]);
        return ans;
    }
    else
    {
        for (int i = 1; i < n; i ++)
        {
            if (protocol[i] == 0)
            {
                add_edge(i, host[i]);
            }
            else
            {
                assert(0);
            }
            /**if (protocol[i] == 2)
            {
                for (int u : adj[host[i]])
                    add_edge(u, i);
            }*/
        }
        ll ans = 0;
        for (int i = 0; i < n; i ++)
        {
            if (!used[i])
            {
                dfs(i, -1);
                ans = ans + max(dp[i][0], dp[i][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