Submission #730394

#	Time	Username	Problem	Language	Result	Execution time	Memory
730394		caganyanmaz	Thousands Islands (IOI22_islands)	C++17	0 / 100	36 ms	3104 KiB

islands

#include <bits/stdc++.h>
#define pb push_back
#define pp pop_back
using namespace std;


vector<int> path;
vector<bool> visited;
vector<vector<int>> g;
vector<array<int, 2>> edges;
vector<int> double_links;
vector<int> result;

bool dfs(int node)
{
        if (visited[node] || double_links[node] != -1)
                return true;
        visited[node] = true;
        for (int edge : g[node])
        {
                path.pb(edge);
                if(dfs(edges[edge][1]))
                        return true;
        }
        path.pp();
        return false;
}

vector<int> create_double_links(vector<array<int, 2>> edges, int n, int m)
{
        sort(edges.begin(), edges.end());
        vector<int> double_links(n, -1);
        for (int i = 0; i < m-1; i++)
                if (edges[i] == edges[i+1])
                        for (int i = 0; i < 2; i++)
                                double_links[edges[i][i]] = edges[i][i^1];
        return double_links;
}


variant<bool, vector<int>> find_journey(int n, int m, vector<int> u, vector<int> v)
{
        if (n > 2)
                return true;
        result.clear();
        path.clear();
        visited = vector<bool>(n, false);
        edges = vector<array<int, 2>>(m);
        for (int i = 0; i < m; i++)
                cin >> edges[i][0] >> edges[i][1];
        double_links = create_double_links(edges, n, m);
        g = vector<vector<int>>(n);
        for (int i = 0; i < m; i++)
                g[edges[i][0]].pb(i);
        if(dfs(0))
                return result;
        return false;
}

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