Submission #374548

#	Time	Username	Problem	Language	Result	Execution time	Memory
374548		idk321	Friend (IOI14_friend)	C++11	46 / 100	30 ms	1516 KiB

friend

#include "friend.h"

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;

const int N = 1005;
vector<int> adj[N];

// Find out best sample

int dp[N][2];
int* conf;
int n;
bool open[N];

int dfs(int node, int par)
{

    dp[node][0] = 0;
    dp[node][1] = conf[node];

    for (int next : adj[node])
    {
        if (next == par) continue;

        dfs(next, node);
        dp[node][0] += max(dp[next][0], dp[next][1]);
        dp[node][1] += dp[next][0];
    }

    return max(dp[node][0], dp[node][1]);
}

bool legal(int node)
{
    for (int next : adj[node])
    {
        if (open[next]) return false;
    }

    return true;
}

int go(int i, int sum)
{
    if (i == n)
    {
        bool ok = true;
        for (int j = 0;  j< n; j++) if (open[j])ok = ok && legal(j);

        if (ok) return sum;
        return 0;
    }

    int best = 0;
    best = max(best, go(i + 1, sum));
    open[i] = true;
    best = max(best, go(i + 1, sum + conf[i]));
    open[i] = false;

    return best;
}



int findSample(int n1,int conf1[],int host[],int pro[]){
    n = n1;
    conf = conf1;
	int ans=10;

    int freq[3] = {};
    for (int i = 1; i < n; i++) freq[pro[i]]++;

    if (freq[0] == 0 && freq[2] == 0)
    {
        int sum = 0;
        for (int i = 0; i < n; i++) sum += conf[i];
        return sum;
    } else if (freq[0] == 0 && freq[1] == 0)
    {
        int res = 0;
        for (int i = 0; i < n; i++) res = max(res, conf[i]);

        return res;
    } else if (freq[1] == 0 &&  freq[2] == 0)
    {
        for (int i = 1; i < n; i++)
        {
            adj[i].push_back(host[i]);
            adj[host[i]].push_back(i);
        }

        return dfs(0, -1);
    } else if (n <= 10)
    {
        for (int i = 1; i < n; i++)
        {
            if (pro[i] == 0)
            {
                adj[i].push_back(host[i]);
                adj[host[i]].push_back(i);
            } else if (pro[i] == 1)
            {
                for (int j : adj[host[i]])
                {
                    adj[i].push_back(j);
                    adj[j].push_back(i);
                }
            } else
            {
                for (int j : adj[host[i]])
                {
                    adj[i].push_back(j);
                    adj[j].push_back(i);
                }

                adj[i].push_back(host[i]);
                adj[host[i]].push_back(i);
            }
        }

        return go(0, 0);
    }

	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