Submission #825481

#	Time	Username	Problem	Language	Result	Execution time	Memory
825481		Liudas	Thousands Islands (IOI22_islands)	C++17	10.15 / 100	31 ms	4560 KiB

islands

#include "islands.h"
#include <cassert>
#include <fstream>
#include <cstdio>
#include <variant>
#include <vector>
#include <map>
#include <set> 
#include <queue>
#include <unordered_set>
#include <algorithm>
#include <iostream>
using namespace std;
variant<bool, vector<int>> find_journey(int N, int M, vector<int> U, vector<int> V) {
    vector<queue<int>> tree(N);
    for(int i = 0; i < M; i ++){
        tree[U[i]].push(V[i]);
    }
    vector<int> path1, path2, vis(N, 0);
    path1.push_back(0);
    while(path1.size()){
        vis[path1.back()] = true;
        if(tree[path1.back()].size()){
            int a = tree[path1.back()].front();
            tree[path1.back()].pop();
            path1.push_back(a);
            if(vis[path1.back()])break;
        }
        else{
            vis[path1.back()] = false;
            path1.pop_back();
        }
    }
    for(int i : path1){
        path2.push_back(i);
        while(path2.size()){
            vis[path2.back()] = true;
            if(tree[path2.back()].size()){
                int a = tree[path2.back()].front();
                tree[path2.back()].pop();
                path2.push_back(a);
                if(vis[path2.back()])break;
            }
            else{
                vis[path2.back()] = false;
                path2.pop_back();
            }
        }
        vis[i] = true;
        if(path2.size())break;
    }
    if(path1.size() && path2.size()){
        return path1;
    }
    return false;
}

• Subtask 1: 0 / 5
• Subtask 2: 1.75 / 5
• Subtask 3: 0 / 21
• Subtask 4: 8.399999999999999 / 24
• Subtask 5: 0 / 45