Submission #1058842

#	Time	Username	Problem	Language	Result	Execution time	Memory
1058842		qwusha	Keys (IOI21_keys)	C++17	37 / 100	3030 ms	174984 KiB

keys

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define fi first
#define se second
typedef long double ld;
const ld eps = 1e-8;
mt19937 rnd(chrono::high_resolution_clock::now().time_since_epoch().count());
const ll inf = 1e18;
const ll mod = 1e9 + 7;

#include "keys.h"


vector<set<int>> g;
vector<vector<pair<int, int>>> gr;
vector<int> num;
int cnt = 0;

void dfs(int v, int number) {
    num[v] = number;
    cnt++;
    for (auto u : g[v]) {
        if (num[u] == -1) {
            dfs(u, number);
        }
    }
}

vector<int> find_reachable(vector<int> r, vector<int> fir, vector<int>sec, vector<int> c) {
    bool first = 1;
    int n = r.size();
    int m = fir.size();
    for (int i = 0; i < m; i++) {
        if (c[i] != 0)
            first = 0;
    }
    if (1) {
        gr.resize(n);
        for (int i = 0; i < m; i++) {
            gr[fir[i]].push_back({sec[i], c[i]});
            gr[sec[i]].push_back({fir[i], c[i]});
        }
        vector<int> p(n);
        set<int> keys;
        set<int> pos;
        vector<int> used(n);
        vector<int> clear_used;
        set<int> clear_reach;
        vector<set<int>> reach(n);
        vector<set<int>> was_reached(n);
        int mini = n + 1;
        vector<int> nodes(n);
        for (int i = 0; i < n; i++) {
            nodes[i] = i;
        }
        random_device rd;
        mt19937 meow(rd());
        shuffle(nodes.begin(), nodes.end(), meow);
        for (int j = 0; j < n; j++) {
            int i = nodes[j];
            keys = {r[i]};
            pos = {i};
            for (auto ind : clear_used)
                used[ind] = 0;
            for (auto ind : clear_reach)
                reach[ind].clear();
            clear_used.clear();
            clear_reach.clear();
            while (!pos.empty()) {
                auto v = *pos.begin();
                pos.erase(pos.begin());
                if (used[v])
                    continue;
                if (was_reached[i].find(v) != was_reached[i].end()) {
                    p[i] = p[v];
                    break;
                }
                was_reached[v].insert(i);
                p[i]++;
                used[v] = 1;
                clear_used.push_back(v);
                if (p[i] > mini) {
                    break;
                }
                if (keys.find(r[v]) == keys.end()) {
                    keys.insert(r[v]);
                    for (auto nod : reach[r[v]]) {
                        if (!used[nod])
                            pos.insert(nod);
                    }
                }
                for (auto [u, w] : gr[v]) {
                    if (!used[u]) {
                        if (keys.find(w) != keys.end()) {
                            pos.insert(u);
                        } else {
                            reach[w].insert(u);
                            clear_reach.insert(w);
                        }
                    }
                }
            }
            mini = min(mini, p[i]);
        }
        vector<int> res(n);
        for (int i = 0; i < n; i++) {
            if (p[i] == mini)
                res[i] = 1;
        }
        return res;
    }
}

/*
int main() {
    vector<int> r = {0, 1, 1, 2, 2, 1, 2},
    u = {0, 0, 1, 1, 2, 3, 3, 4, 4, 5},
    v = {1, 2, 2, 3, 3, 4, 5, 5, 6, 6},
    c = {0, 0, 1, 0, 0, 1, 2, 0, 2, 1};

    auto res = find_reachable(r,u,v,c);
    for (int i = 0; i < r.size(); i++) {
        cout << res[i] << ' ';
    }
}
*/

Compilation message (stderr)

keys.cpp: In function 'std::vector<int> find_reachable(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
keys.cpp:31:10: warning: variable 'first' set but not used [-Wunused-but-set-variable]
   31 |     bool first = 1;
      |          ^~~~~

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