Submission #842023

#	Time	Username	Problem	Language	Result	Execution time	Memory
842023		Tenis0206	Longest Trip (IOI23_longesttrip)	C++17	0 / 100	7 ms	344 KiB

longesttrip

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

using namespace std;

const int nmax = 256;

int n;

std::vector<int> G[nmax + 5];

vector<int> r;

int d[nmax + 5];

void bfs(int nod)
{
    queue<int> q;
    for(int i=0;i<n;i++)
    {
        d[i] = 0;
    }
    d[nod] = 1;
    q.push(nod);
    while(!q.empty())
    {
        nod = q.front();
        q.pop();
        for(auto it : G[nod])
        {
            if(d[it])
            {
                continue;
            }
            d[it] = 1 + d[nod];
            q.push(it);
        }
    }
    for(int i=0;i<n;i++)
    {
        if(d[i] > d[nod])
        {
            nod = i;
        }
    }
    vector<int> aux;
    aux.push_back(nod);
    while(d[nod]!=1)
    {
        for(auto it : G[nod])
        {
            if(d[it]==d[nod] - 1)
            {
                nod = it;
                break;
            }
        }
        aux.push_back(nod);
    }
    if(aux.size() > r.size())
    {
        r = aux;
    }
}

std::vector<int> longest_trip(int N, int D)
{
    n = N;
    r.clear();
    for(int i=0;i<n;i++)
    {
        G[i].clear();
    }
    for(int i=0; i<n; i++)
    {
        for(int j=i+1; j<n; j++)
        {
            if(are_connected({i}, {j}))
            {
                G[i].push_back(j);
                G[j].push_back(i);
            }
        }
    }
    for(int i=0;i<n;i++)
    {
        bfs(i);
    }
    return r;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 25
• Subtask 4: 0 / 60