Submission #922977

# Submission time Handle Problem Language Result Execution time Memory
922977 2024-02-06T11:28:35 Z vjudge1 Olympic Bus (JOI20_ho_t4) C++17
100 / 100
146 ms 4040 KB
// #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 = (1e15) + 500;
const int BIG = (2e9) + 500;
const int MOD7 = (1e9) + 7;
const int MOD9 = (1e9) + 9;
const uint MODFFT = 998244353;

// #define int ll

struct test
{
    vector<vector<pll>> graph, invgraph;
    vector<int> components;
    int n, m;

    void merge(pll &a, ll val)
    {
        if (a.f > val)
        {
            a.s = a.f;
            a.f = val;
        }
        else
            a.s = min(a.s, val);
    }

    vector<int> used;
    void dijkstra(vector<ll> &dists, int st, int U, int V, ll C)
    {
        for (int i = 0; i < n; ++i)
            dists[i] = INF, used[i] = 0;
        dists[st] = 0;
        for (int i = 0; i < n; ++i)
        {
            int v = -1;
            for (int i = 0; i < n; ++i)
                if (!used[i] and (v == -1 or dists[v] > dists[i]))
                    v = i;
            if (v == -1)
                break;
            used[v] = 1;
            for (int i = 0; i < n; ++i)
                if (!used[i])
                {
                    ll cost;
                    if (U == v and V == i and graph[v][i].f == C)
                        cost = graph[v][i].s;
                    else
                        cost = graph[v][i].f;

                    if (U == i and V == v)
                        cost = min(cost, C);

                    dists[i] = min(dists[i], dists[v] + cost);
                }
        }
    }

    void invdijkstra(vector<ll> &dists, int st, int U, int V, ll C)
    {
        for (int i = 0; i < n; ++i)
            dists[i] = INF, used[i] = 0;
        dists[st] = 0;
        for (int i = 0; i < n; ++i)
        {
            int v = -1;
            for (int i = 0; i < n; ++i)
                if (!used[i] and (v == -1 or dists[v] > dists[i]))
                    v = i;
            if (v == -1)
                break;
            used[v] = 1;
            for (int i = 0; i < n; ++i)
                if (!used[i])
                {
                    ll cost = (U == v and V == i and invgraph[v][i].f == C ? invgraph[v][i].s : invgraph[v][i].f);
                    dists[i] = min(dists[i], dists[v] + cost);
                }
        }
    }

    vector<pii> E;
    vector<int> WAS;

    bool dfs(int v, int fn, vector<ll> &dist)
    {
        WAS[v] = 1;
        if (v == fn)
            return true;
        for (int tov = 0; tov < n; ++tov)
            if (!WAS[tov] and dist[v] == dist[tov] + graph[v][tov].f and dfs(tov, fn, dist))
            {
                E.pb({v, tov});
                return true;
            }
        return false;
    }

    void solve(int testcase)
    {
        boost();

        cin >> n >> m;

        WAS.resize(n);
        used.resize(n);
        graph.resize(n, vector<pll>(n, {INF, INF}));
        invgraph.resize(n, vector<pll>(n, {INF, INF}));

        vector<pair<pii, pii>> edges;

        for (int i = 0; i < m; ++i)
        {
            int v, tov, c, d;
            cin >> v >> tov >> c >> d;
            --v, --tov;
            merge(graph[v][tov], c);
            merge(invgraph[tov][v], c);
            edges.pb({{d, c}, {v, tov}});
        }
        sort(all(edges));

        vector<ll> dist0(n, INF), distN(n, INF), to0(n, INF), toN(n, INF);

        dijkstra(dist0, 0, 0, 0, 0);
        dijkstra(distN, n - 1, 0, 0, 0);
        invdijkstra(to0, 0, 0, 0, 0);
        invdijkstra(toN, n - 1, 0, 0, 0);

        vector<ll> bf(n);

        ll res = INF;
        if (dist0[n - 1] == INF and distN[n - 1] == INF)
        {
            for (auto [e1, e2] : edges)
            {
                auto [v, tov] = e2;
                auto [d, c] = e1;
                res = min(res, d + dist0[tov] + c + toN[v] + distN[tov] + c + to0[v]);
            }
        }
        else
        {
            map<pair<pii, ll>, ll> bad;

            int CC = 0;

            if (dist0[n - 1] != INF)
            {
                WAS.assign(n, 0);
                E.clear();
                assert(dfs(0, n - 1, toN));

                // reverse(all(E));
                // cout << E << " " << dist0[n - 1] << "!!\n";

                for (auto [v, tov] : E)
                {
                    CC++;
                    // if (CC > 2 * n + 10)
                    //     exit(0);
                    ll curRes = 0;
                    dijkstra(bf, 0, v, tov, graph[v][tov].f);
                    curRes += bf[n - 1];
                    dijkstra(bf, n - 1, v, tov, graph[v][tov].f);
                    curRes += bf[0];
                    bad[{{v, tov}, graph[v][tov].f}] = curRes;
                }
            }
            if (distN[0] != INF)
            {
                WAS.assign(n, 0);
                E.clear();
                assert(dfs(n - 1, 0, to0));

                // reverse(all(E));
                // cout << E << " " << distN[0] << "!!\n";

                for (auto [v, tov] : E)
                {
                    // if (CC > 2 * n + 10)
                    //     exit(0);
                    ll curRes = 0;
                    dijkstra(bf, 0, v, tov, graph[v][tov].f);
                    curRes += bf[n - 1];
                    dijkstra(bf, n - 1, v, tov, graph[v][tov].f);
                    curRes += bf[0];
                    bad[{{v, tov}, graph[v][tov].f}] = curRes;
                }
            }
            ll way0N = dist0[n - 1];
            ll wayN0 = distN[0];
            res = min(res, way0N + wayN0);

            for (auto [e1, e2] : edges)
            {
                auto [v, tov] = e2;
                auto [d, c] = e1;
                if (bad.find({{v, tov}, c}) != bad.end())
                    res = min(res, d + bad[{{v, tov}, c}]);
                else
                    res = min(res, d + min(way0N, dist0[tov] + c + toN[v]) + min(wayN0, distN[tov] + c + to0[v]));
            }
        }

        if (res == INF)
            cout << "-1\n";
        else
            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                                  //
//                                                                                    //
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//

Compilation message

ho_t4.cpp:297:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  297 | main()
      | ^~~~
# Verdict Execution time Memory Grader output
1 Correct 55 ms 1624 KB Output is correct
2 Correct 2 ms 1628 KB Output is correct
3 Correct 5 ms 1628 KB Output is correct
4 Correct 6 ms 1628 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 1628 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 460 KB Output is correct
9 Correct 1 ms 344 KB Output is correct
10 Correct 114 ms 2024 KB Output is correct
11 Correct 111 ms 1624 KB Output is correct
12 Correct 115 ms 2024 KB Output is correct
13 Correct 2 ms 1628 KB Output is correct
14 Correct 5 ms 1780 KB Output is correct
15 Correct 4 ms 1628 KB Output is correct
16 Correct 5 ms 1784 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 20 ms 3540 KB Output is correct
2 Correct 22 ms 3688 KB Output is correct
3 Correct 20 ms 3792 KB Output is correct
4 Correct 4 ms 1624 KB Output is correct
5 Correct 6 ms 1748 KB Output is correct
6 Correct 2 ms 1628 KB Output is correct
7 Correct 2 ms 1628 KB Output is correct
8 Correct 0 ms 348 KB Output is correct
9 Correct 18 ms 3796 KB Output is correct
10 Correct 21 ms 3796 KB Output is correct
11 Correct 23 ms 3668 KB Output is correct
12 Correct 22 ms 3660 KB Output is correct
13 Correct 20 ms 3792 KB Output is correct
14 Correct 22 ms 3796 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 31 ms 1624 KB Output is correct
2 Correct 7 ms 1628 KB Output is correct
3 Correct 56 ms 3540 KB Output is correct
4 Correct 1 ms 1628 KB Output is correct
5 Correct 64 ms 3540 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 452 KB Output is correct
8 Correct 17 ms 3540 KB Output is correct
9 Correct 19 ms 3536 KB Output is correct
10 Correct 62 ms 3540 KB Output is correct
11 Correct 25 ms 3540 KB Output is correct
12 Correct 22 ms 3540 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 0 ms 348 KB Output is correct
16 Correct 0 ms 392 KB Output is correct
17 Correct 0 ms 348 KB Output is correct
18 Correct 0 ms 348 KB Output is correct
19 Correct 57 ms 3616 KB Output is correct
20 Correct 36 ms 3540 KB Output is correct
21 Correct 22 ms 3576 KB Output is correct
22 Correct 31 ms 3540 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 55 ms 1624 KB Output is correct
2 Correct 2 ms 1628 KB Output is correct
3 Correct 5 ms 1628 KB Output is correct
4 Correct 6 ms 1628 KB Output is correct
5 Correct 1 ms 348 KB Output is correct
6 Correct 1 ms 1628 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 0 ms 460 KB Output is correct
9 Correct 1 ms 344 KB Output is correct
10 Correct 114 ms 2024 KB Output is correct
11 Correct 111 ms 1624 KB Output is correct
12 Correct 115 ms 2024 KB Output is correct
13 Correct 2 ms 1628 KB Output is correct
14 Correct 5 ms 1780 KB Output is correct
15 Correct 4 ms 1628 KB Output is correct
16 Correct 5 ms 1784 KB Output is correct
17 Correct 20 ms 3540 KB Output is correct
18 Correct 22 ms 3688 KB Output is correct
19 Correct 20 ms 3792 KB Output is correct
20 Correct 4 ms 1624 KB Output is correct
21 Correct 6 ms 1748 KB Output is correct
22 Correct 2 ms 1628 KB Output is correct
23 Correct 2 ms 1628 KB Output is correct
24 Correct 0 ms 348 KB Output is correct
25 Correct 18 ms 3796 KB Output is correct
26 Correct 21 ms 3796 KB Output is correct
27 Correct 23 ms 3668 KB Output is correct
28 Correct 22 ms 3660 KB Output is correct
29 Correct 20 ms 3792 KB Output is correct
30 Correct 22 ms 3796 KB Output is correct
31 Correct 31 ms 1624 KB Output is correct
32 Correct 7 ms 1628 KB Output is correct
33 Correct 56 ms 3540 KB Output is correct
34 Correct 1 ms 1628 KB Output is correct
35 Correct 64 ms 3540 KB Output is correct
36 Correct 0 ms 348 KB Output is correct
37 Correct 0 ms 452 KB Output is correct
38 Correct 17 ms 3540 KB Output is correct
39 Correct 19 ms 3536 KB Output is correct
40 Correct 62 ms 3540 KB Output is correct
41 Correct 25 ms 3540 KB Output is correct
42 Correct 22 ms 3540 KB Output is correct
43 Correct 0 ms 348 KB Output is correct
44 Correct 0 ms 348 KB Output is correct
45 Correct 0 ms 348 KB Output is correct
46 Correct 0 ms 392 KB Output is correct
47 Correct 0 ms 348 KB Output is correct
48 Correct 0 ms 348 KB Output is correct
49 Correct 57 ms 3616 KB Output is correct
50 Correct 36 ms 3540 KB Output is correct
51 Correct 22 ms 3576 KB Output is correct
52 Correct 31 ms 3540 KB Output is correct
53 Correct 20 ms 3540 KB Output is correct
54 Correct 22 ms 3540 KB Output is correct
55 Correct 24 ms 3540 KB Output is correct
56 Correct 5 ms 1628 KB Output is correct
57 Correct 3 ms 1628 KB Output is correct
58 Correct 126 ms 3488 KB Output is correct
59 Correct 129 ms 3536 KB Output is correct
60 Correct 125 ms 3540 KB Output is correct
61 Correct 105 ms 3540 KB Output is correct
62 Correct 134 ms 3536 KB Output is correct
63 Correct 129 ms 3540 KB Output is correct
64 Correct 146 ms 3540 KB Output is correct
65 Correct 129 ms 3536 KB Output is correct
66 Correct 123 ms 3540 KB Output is correct
67 Correct 13 ms 2336 KB Output is correct
68 Correct 19 ms 3792 KB Output is correct
69 Correct 20 ms 3792 KB Output is correct
70 Correct 21 ms 3796 KB Output is correct
71 Correct 21 ms 3796 KB Output is correct
72 Correct 23 ms 4040 KB Output is correct
73 Correct 20 ms 3796 KB Output is correct
74 Correct 22 ms 3692 KB Output is correct