제출 #928260

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
928260		vjudge1	Amusement Park (CEOI19_amusementpark)	C++17	19 / 100	3057 ms	600 KiB

amusementpark

// #pragma GCC target("avx2")
// #pragma GCC optimize("O3")
// #include <x86intrin.h>

#include <bits/stdc++.h>
#include <chrono>
#include <random>

// @author: Vlapos

namespace operators
{
    template <typename T1, typename T2>
    std::istream &operator>>(std::istream &in, std::pair<T1, T2> &x)
    {
        in >> x.first >> x.second;
        return in;
    }

    template <typename T1, typename T2>
    std::ostream &operator<<(std::ostream &out, std::pair<T1, T2> x)
    {
        out << x.first << " " << x.second;
        return out;
    }

    template <typename T1>
    std::istream &operator>>(std::istream &in, std::vector<T1> &x)
    {
        for (auto &i : x)
            in >> i;
        return in;
    }

    template <typename T1>
    std::ostream &operator<<(std::ostream &out, std::vector<T1> &x)
    {
        for (auto &i : x)
            out << i << " ";
        return out;
    }

    template <typename T1>
    std::ostream &operator<<(std::ostream &out, std::set<T1> &x)
    {
        for (auto &i : x)
            out << i << " ";
        return out;
    }
}

// name spaces
using namespace std;
using namespace operators;
// end of name spaces

// defines
#define ll long long
#define ull unsigned long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define f first
#define s second
#define uint unsigned int
#define all(vc) vc.begin(), vc.end()
// end of defines

// usefull stuff

void boost()
{
    ios_base ::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}

inline int getbit(int &x, int &bt) { return (x >> bt) & 1; }

const int dx4[4] = {-1, 0, 0, 1};
const int dy4[4] = {0, -1, 1, 0};
const int dx8[8] = {-1, -1, -1, 0, 0, 1, 1, 1};
const int dy8[8] = {-1, -0, 1, -1, 1, -1, 0, 1};

const ll INF = (1e18) + 500;
const int BIG = (1e9) * 2 + 100;
const int MAXN = (1e5) + 5;
const int MOD7 = (1e9) + 7;
const int MOD9 = (1e9) + 9;
const uint MODFFT = 998244353;

#define int ll

struct test
{
    vector<vector<int>> graph;
    vector<int> was;
    int n, m;

    bool dfs(int v)
    {
        was[v] = 1;
        for (int i = 0; i < n; ++i)
            if (graph[v][i] and was[i] != 2)
            {
                if (was[i] == 1 or !dfs(i))
                    return false;
            }
        was[v] = 2;
        return true;
    }

    void solve(int testcase)
    {
        boost();

        cin >> n >> m;

        was.resize(n);
        graph.resize(n, vector<int>(n));
        vector<pii> edges;

        for (int i = 0; i < m; ++i)
        {
            int v, tov;
            cin >> v >> tov;
            --v, --tov;
            edges.pb({v, tov});
            graph[v][tov] = 1;
        }

        int res = 0;
        for (int mask = 0; mask < (1 << m); ++mask)
        {
            int cnt = 0;
            for (int i = 0; i < m; ++i)
                if (mask & (1 << i))
                {
                    graph[edges[i].f][edges[i].s] = 0, graph[edges[i].s][edges[i].f] = 1;
                    cnt++;
                }

            bool good = true;
            fill(all(was), 0);
            for (int i = 0; i < n; ++i)
                if (!was[i])
                    good &= dfs(i);

            if (good)
                res += cnt;

            for (int i = 0; i < m; ++i)
                if (mask & (1 << i))
                    graph[edges[i].f][edges[i].s] = 1,
                    graph[edges[i].s][edges[i].f] = 0;
        }
        cout << res << "\n";
    }
};

main()
{
    boost();
    int q = 1;
    // cin >> q;
    for (int i = 0; i < q; i++)
    {
        test t;
        t.solve(i);
    }
    return 0;
}
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//
//                                                                                    //
//                               Coded by Der_Vlἀpos                                  //
//                                                                                    //
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//

컴파일 시 표준 에러 (stderr) 메시지

amusementpark.cpp:162:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  162 | main()
      | ^~~~

• Subtask 1: 7 / 7
• Subtask 2: 12 / 12
• Subtask 3: 0 / 23
• Subtask 4: 0 / 21
• Subtask 5: 0 / 37