Submission #1248941

#	Time	Username	Problem	Language	Result	Execution time	Memory
1248941		madamadam3	Longest Trip (IOI23_longesttrip)	C++20	5 / 100	5 ms	416 KiB

longesttrip

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

using namespace std;

using vi = vector<int>;
using vvi = vector<vi>;

vi longest_trip(int N, int D) {
    int n = N, d = D;
    vi ans;

    if (d == 3) {
        ans.resize(n); iota(ans.begin(), ans.end(), 0);
        return ans; 
    } else if (d == 1) {
        int a = 0, b = 1;
        vi p1(1, a), p2(1, b);

        for (int i = 2; i < n; i++) {
            if (are_connected({a}, {i})) {
                p1.push_back(i);
                a = i;
            } else if (are_connected({b}, {i})) {
                p2.push_back(i);
                b = i;
            } else {
                while (!p2.empty()) {
                    p1.push_back(p2.back());
                    p2.pop_back();
                }

                a = p1.back();
                p2.push_back(i);
                b=i;
            }
        }

        if (!are_connected(p1, p2)) {
            return p1.size() > p2.size() ? p1 : p2;
        } else {
            if (are_connected({p1[0]}, {p2[0]})) {
                reverse(p1.begin(), p1.end());
                for (auto &el : p2) p1.push_back(el);
                return p1;
            } else if (are_connected({p1[0]}, {p2.back()})) {
                swap(p1, p2);
                for (auto &el : p2) p1.push_back(el);
                return p1;
            } else if (are_connected({p1.back()}, {p2[0]})) {
                for (auto &el : p2) p1.push_back(el);
                return p1; 
            } else if (are_connected({p1.back()}, {p2.back()})) {
                reverse(p2.begin(), p2.end());
                for (auto &el : p2) p1.push_back(el);
                return p1;
            } else {
                for (int i = 0; i < p2.size(); i++) {
                    if (are_connected({p2[i]}, {p1.back()})) {
                        for (int j = i; j < p2.size(); j++) p1.push_back(p2[j]);
                        for (int j = 0; j < i; j++) p1.push_back(p2[j]);
                        return p1;
                    }
                }
            }
        }
    }

    return ans;
}

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