Submission #840596

#	Time	Username	Problem	Language	Result	Execution time	Memory
840596		danikoynov	Longest Trip (IOI23_longesttrip)	C++17	15 / 100	1016 ms	848 KiB

longesttrip

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

const int maxn = 260;
vector < int > adj[maxn];
int used[maxn], edge[maxn][maxn];

int n;
void dfs(int v, int c)
{
    used[v] = c;
    for (int u : adj[v])
    {
        if (!used[u])
            dfs(u, c);

    }
}

int deg[maxn];
vector<int> longest_trip(int N, int D)
{
    n = N;
    if (n == 0)
        return {};
    if (D == 3)
    {
        vector < int > r;
        for (int i = 0; i < N; i ++)
            r.push_back(i);
        return r;
    }

    for (int i = 0; i < N; i ++)
        adj[i].clear();

    for (int i = 0; i < N; i ++)
        used[i] = 0, deg[i] = 0;
    for (int i = 0; i < N; i ++)
        for (int j = i + 1; j < N; j ++)
        {
            vector < int > a, b;
            a.push_back(i);
            b.push_back(j);
            if (are_connected(a, b))
            {
                adj[i].push_back(j);
                adj[j].push_back(i);
                edge[i][j] = 1;
                edge[j][i] = 1;
                deg[i] ++;
                deg[j] ++;
            }
        }


    int cp = 0;
    for (int i = 0; i < N; i ++)
    {
        if (!used[i])
            dfs(i, ++ cp);
    }

    if (cp == 2)
    {

        vector < int > a, b;
        for (int i = 0; i < N; i ++)
            if (used[i] == 1)
                a.push_back(i);
            else
                b.push_back(i);
        if (a.size() > b.size())
            return a;
        return b;
    }


    vector < int > res;
    int tk = 0;
    while(tk < N && deg[tk] != 1)
        tk ++;
    if (tk == N)
        tk = 0;


    for (int step = 0; step < N; step ++)
    {

        res.push_back(tk);
        int nxt = -1;
        for (int u = 0; u < N; u ++)
        {
            if (edge[tk][u])
            {
                deg[u] --;
                if (deg[u] == 1 || nxt == -1)
                    nxt = u;
                deg[tk] --;
                edge[tk][u] = edge[u][tk] = 0;
            }
        }
        tk = nxt;


    }
    return res;
}

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