Submission #1187748

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187748		MatteoArcari	Longest Trip (IOI23_longesttrip)	C++20	25 / 100	5 ms	420 KiB

longesttrip

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

bool are_connected(vector<int> A, vector<int> B);

vector<int> connect(vector<int> a, vector<int> b) {
    reverse(a.begin(), a.end());
    for (auto x: b) a.push_back(x);
    return a;
}

vector<int> longest_trip(int n, int d) {
    vector<vector<int>> paths = {{0}, {1}, {2}};
    for (int i = 3; i < n; i++) {
        bool flag = 1;
        for (int k: {0, 1, 2}) {
            if (are_connected({paths[k].back()}, {i})) {
                paths[k].push_back(i);
                flag = 0;
                break;
            }
        }
        if (flag) {
            vector<int> pathA, pathB;

            if (are_connected({paths[0][0]}, {paths[1][0]})) {
                pathA = connect(paths[0], paths[1]);
                pathB = paths[2];
            } else if (are_connected({paths[0][0]}, {paths[2][0]})) {
                pathA = connect(paths[0], paths[2]);
                pathB = paths[1];
            } else {
                pathA = connect(paths[2], paths[1]);
                pathB = paths[0];
            } 
            paths[0] = pathA;
            paths[1] = pathB;
            paths[2] = {i};
        }
    }
    vector<int> pathA, pathB;

    if (are_connected({paths[0][0]}, {paths[1][0]})) {
        pathA = connect(paths[0], paths[1]);
        pathB = paths[2];
    } else if (are_connected({paths[0][0]}, {paths[2][0]})) {
        pathA = connect(paths[0], paths[2]);
        pathB = paths[1];
    } else {
        pathA = connect(paths[2], paths[1]);
        pathB = paths[0];
    } 

    if (pathA.size() > pathB.size()) return pathA;
    return pathB;
}

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