Submission #1308742

#	Time	Username	Problem	Language	Result	Execution time	Memory
1308742		ofoz	Island Hopping (JOI24_island)	C++20	65 / 100	4 ms	452 KiB

island

#include <bits/stdc++.h>
using namespace std;
#include "island.h"
#define vc vector<char>
#define vi vector<int>
#define vii vector<vi>
#define viii vector<vii>
#define viiii vector<viii>
#define viiiii vector<viiii>
#define vb vector<bool>
#define pi pair<double, double>

void dfs(int v, int p, vb& vis, vii& adj, bool& res) {
    if (vis[v]) { res = 1; return; }
    vis[v] = 1;
    for (int to : adj[v]) {
        if (to == p) continue;
        dfs(to, v, vis, adj, res);
    } 
}

bool hasCycle(vii& adj) {
    int n = adj.size()-1;
    bool res = 0;
    vb vis(n+1, 0);
    for (int v = 1; v <= n; v++) {
        if (!vis[v]) dfs(v, -1, vis, adj, res);
    }
    return res;
}



void solve(int n, int L) {
    vb sol(n+1, 0);
    vector<vb> edge(n+2, vb(n+2, 0));
    vii adj(n+1);
    int cnt = 0;
    auto addEdge = [&](int a, int b) {
        if (edge[a][b]) return;
        adj[a].push_back(b);
        adj[b].push_back(a);
        edge[a][b] = edge[b][a] = 1;
        cnt++;
        answer(a, b);
    };
    
    for (int v = n; v >= 1; v--) {
        int sum = 0;
        for (int x : sol) sum += x;
        if (sum == n-1) break;
        if (sol[v]) {
            for (int q : adj[v]) {
                if (q > v) continue;
                if (sol[q]) continue;
                for (int k2 = 1; k2 < n; k2++) {
                    int q2 = query(q, k2);
                    if (q2 >= v) break;
                    addEdge(q, q2);
                    if (cnt == n-1) break;
                }
                if (cnt == n-1) break;
                sol[q] = 1;

            }
            if (cnt == n-1) break;
            continue;
        }
        for (int k = 1; k < n; k++) {
            int q = query(v, k);
            if (!edge[v][q]) {
                adj[v].push_back(q);
                adj[q].push_back(v);
                bool b = hasCycle(adj);
                adj[v].pop_back();
                adj[q].pop_back();
                if (b) break;
            }
            if (q > v) break;
            if (sol[q]) continue;
            

            addEdge(v, q);
            if (cnt == n-1) break;
            for (int k2 = 1; k2 < n; k2++) {
                int q2 = query(q, k2);
                if (q2 >= v) break;
                addEdge(q, q2);
                if (cnt == n-1) break;
            }

            sol[q] = 1;
            if (cnt == n-1) break;
        }
        sol[v] = 1;
    }
}

• Subtask 1: 2 / 2
• Subtask 2: 4 / 4
• Subtask 3: 0 / 7
• Subtask 4: 9 / 9
• Subtask 5: 13 / 13
• Subtask 6: 15 / 15
• Subtask 7: 22 / 22
• Subtask 8: 0 / 28