Submission #1213432

#	Time	Username	Problem	Language	Result	Execution time	Memory
1213432		omsincoconut	Keys (IOI21_keys)	C++17	9 / 100	3096 ms	24808 KiB

keys

#include <bits/stdc++.h>

using namespace std;

vector<int> find_reachable(vector<int> r, vector<int> u, vector<int> v, vector<int> c) {
    int n = r.size(), m = u.size();

    vector<vector<pair<int, int>>> edge(n);
    for (int i = 0; i < m; i++) {
        edge[u[i]].emplace_back(v[i], c[i]);
        edge[v[i]].emplace_back(u[i], c[i]);
    }

    vector<int> p(n);
    for (int i = 0; i < n; i++) {
        queue<int> bfs;
        vector<vector<int>> pending(n);
        vector<int> colored(n), vis(n);

        bfs.push(i);
        while (!bfs.empty()) {
            int u = bfs.front();
            bfs.pop();
            if (vis[u]) continue;
            vis[u] = true;

            if (!colored[r[u]]) {
                colored[r[u]] = true;
                for (int v : pending[r[u]]) bfs.push(v);
                pending[r[u]].clear();
            }

            for (auto [v, c] : edge[u]) {
                if (colored[c]) bfs.push(v);
                else pending[c].push_back(v);
            }
        }

        p[i] = accumulate(vis.begin(), vis.end(), 0);
    }

    int min_p = *min_element(p.begin(), p.end());

    vector<vector<int>> edge2(n);
    for (int i = 0; i < m; i++) {
        if (r[u[i]] == c[i]) edge2[u[i]].push_back(v[i]);
        if (r[v[i]] == c[i]) edge2[v[i]].push_back(u[i]);
    }

    vector<int> p2(n);
    for (int i = 0; i < n; i++) {
        queue<int> bfs;
        vector<int> vis(n);

        bfs.push(i);
        while (!bfs.empty()) {
            int u = bfs.front();
            bfs.pop();
            if (vis[u]) continue;
            vis[u] = true;

            for (int v : edge2[u]) {
                bfs.push(v);
            }
        }

        p2[i] = accumulate(vis.begin(), vis.end(), 0);
    }

    int min_p2 = *min_element(p2.begin(), p2.end());

    vector<vector<int>> edge3(n);
    for (int i = 0; i < m; i++) {
        edge3[u[i]].push_back(v[i]);
        edge3[v[i]].push_back(u[i]);
    }

    vector<int> compid(n, -1);
    int compcnt = 0;
    for (int i = 0; i < n; i++) {
        if (compid[i] > -1) continue;

        queue<int> bfs;
        bfs.push(i);
        while (!bfs.empty()) {
            int u = bfs.front();
            bfs.pop();
            if (compid[u] > -1) continue;
            compid[u] = compcnt;

            for (int v : edge3[u]) {
                bfs.push(v);
            }
        }

        compcnt++;
    }

    vector<vector<int>> comp(compcnt);
    for (int i = 0; i < n; i++) comp[compid[i]].push_back(i);

    vector<int> candidate;
    for (vector<int> cc : comp) {
        int mp2 = (int)1e9;
        for (int v : cc) mp2 = min(mp2, p2[v]);
        for (int v : cc) if (p2[v] == mp2) candidate.push_back(v);
    }

    int mimi = (int)1e9;
    for (int v : candidate) mimi = min(mimi, p2[v]);

    vector<int> ret(n);
    for (int v : candidate) if (p2[v] == mimi) ret[v] = true;
    return ret;
}

• Subtask 1: 9 / 9
• Subtask 2: 0 / 11
• Subtask 3: 0 / 17
• Subtask 4: 0 / 30
• Subtask 5: 0 / 33