Submission #1080604

#	Time	Username	Problem	Language	Result	Execution time	Memory
1080604		asdasdqwer	Thousands Islands (IOI22_islands)	C++17	10 / 100	27 ms	5188 KiB

islands

#include "islands.h"

#include <variant>
#include <vector>

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

std::variant<bool, std::vector<int>> find_journey(int N, int M, std::vector<int> U, std::vector<int> V) {
    variant<bool, vector<int>> ret;
    if (N == 2) {
        vector<vector<int>> boat(N);
        for (int i=0;i<M;i++) {
            boat[U[i]].push_back(i);
        }

        if (boat[0].size() < 2 || boat[1].size() < 1) {
            ret = false;
            ret = {};
            return ret;
        }

        ret = true;
        int f1 = boat[0][0], f2 = boat[0][1], s1 = boat[1][0];
        ret = vector<int>({f1, s1, f2, f1, s1, f2});
        return ret;
    }

    // check if subtask 2
    if (N <= 400) {
        vector<vector<int>> cnt(N, vector<int>(N, 0));
        for (int i=0;i<M;i++) {
            cnt[U[i]][V[i]]++;
        }
        bool ff=true;
        for (int i=0;i<N;i++) {
            for (int j=0;j<N;j++) {
                if (i==j)continue;
                if (cnt[i][j] == 0) ff=false;
            }
        }

        if (ff) {
            vector<int> f1(2), f2(2);
            for (int i=0;i<M;i++) {
                if (U[i] != 0 && V[i] != 0) continue;
                if (U[i] == 1) f1[1] = i;
                else if (V[i] == 1) f1[0]=i;
                if (U[i]  ==  2) f2[1]=i;
                else if (V[i] == 2) f2[0]=i;
            }

            ret = true;
            ret = vector<int>({f1[0], f1[1], f2[0], f2[1], f1[1], f1[0], f2[1], f2[0]});
            return ret;
        }
    }

    return ret;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 21
• Subtask 4: 0 / 24
• Subtask 5: 0 / 45