oj.uz

Submission #443068

# Submission time Handle Problem Language Result Execution time Memory
443068 2021-07-09T15:19:25 Z arujbansal Commuter Pass (JOI18_commuter_pass) C++17
100 / 100
 417 ms 25340 KB 
#include <iostream>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <array>
#include <stack>
#include <queue>
#include <random>
#include <numeric>
#include <functional>
#include <chrono>
#include <utility>
#include <iomanip>
#include <assert.h>

using namespace std;

void dbg_out() { cerr << endl; }
template<typename Head, typename... Tail>
void dbg_out(Head H, Tail... T) { cerr << ' ' << H; dbg_out(T...); }
#define dbg(...) cerr << "(" << #__VA_ARGS__ << "):", dbg_out(__VA_ARGS__)

#define rng_init mt19937 rng(chrono::steady_clock::now().time_since_epoch().count())
#define rng_seed(x) mt19937 rng(x)
#define all(x) (x).begin(), (x).end()
#define sz(x) (int) (x).size()
#define int long long

template<typename T>
struct Dijkstra {
    const T INF = numeric_limits<T>::max();

    struct state {
        int u;
        T dist;

        state() {}

        state(int _u, T _dist) : u(_u), dist(_dist) {}

        bool operator<(const state &other) const {
            return dist > other.dist;
        }
    };

    int n;
    vector<vector<pair<int, T>>> graph;
    vector<T> dist;
    vector<int> parent;

    Dijkstra(int _n = 0) {
        init(_n);
    }

    void init(int _n) {
        n = _n;
        graph.resize(n);
    }

    void add_directional_edge(int u, int v, T weight) {
        graph[u].emplace_back(v, weight);
    }

    void add_bidirectional_edge(int u, int v, T weight) {
        add_directional_edge(u, v, weight);
        add_directional_edge(v, u, weight);
    }

    void run(const vector<int> &source) {
        priority_queue<state> pq;
        dist.assign(n, INF);
        parent.assign(n, -1);

        for (const auto &u : source) {
            dist[u] = 0;
            parent[u] = u;

            pq.emplace(u, 0);
        }

        while (!pq.empty()) {
            auto [u, cur_dist] = pq.top();
            pq.pop();

            if (dist[u] != cur_dist) continue;

            for (const auto &[v, weight] : graph[u]) {
                T new_dist = cur_dist + weight;

                if (new_dist < dist[v]) {
                    dist[v] = new_dist;
                    parent[v] = u;
                    pq.emplace(v, new_dist);
                }
            }
        }
    }

    bool reachable(int u) {
        return dist[u] < INF;
    }
};

const int MXN = 1e5 + 5, INF = 1e18;

void solve() {
    int N, M, S, T, U, V;
    cin >> N >> M >> S >> T >> U >> V;

    Dijkstra<int> solver(N + 1);

    while (M--) {
        int u, v, wt;
        cin >> u >> v >> wt;

        solver.add_bidirectional_edge(u, v, wt);
    }

    solver.run(vector<int>{U});
    vector<int> u_dist = solver.dist;

    int ans = u_dist[V];

    solver.run(vector<int>{V});
    vector<int> v_dist = solver.dist;

    solver.run(vector<int>{S});
    vector<int> s_dist = solver.dist;

    solver.run(vector<int>{T});
    vector<int> t_dist = solver.dist;

    vector<pair<int, int>> dag_order;
    for (int i = 1; i < sz(s_dist); i++)
        dag_order.emplace_back(s_dist[i], i);

    sort(all(dag_order));

    vector<int> dp1(N + 1, INF), dp2(N + 1, INF);

    for (const auto &[cur_dist, node] : dag_order) {
        dp1[node] = u_dist[node];
        dp2[node] = v_dist[node];

        for (const auto &[v, wt] : solver.graph[node]) {
            if (s_dist[v] > s_dist[node]) continue;

            if (s_dist[v] + wt + t_dist[node] == s_dist[T]) {
                ans = min({ans, dp1[v] + v_dist[node], dp2[v] + u_dist[node]});

                dp1[node] = min(dp1[node], dp1[v]);
                dp2[node] = min(dp2[node], dp2[v]);
            }
        }
    }

    cout << ans;
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int TC = 1;
    // cin >> TC;
    while (TC--) solve();
}

Subtask #1
16.0 / 16.0

# Verdict Execution time Memory Grader output
1 Correct 369 ms 25340 KB Output is correct
2 Correct 346 ms 24288 KB Output is correct
3 Correct 356 ms 25084 KB Output is correct
4 Correct 342 ms 25168 KB Output is correct
5 Correct 399 ms 24276 KB Output is correct
6 Correct 370 ms 25244 KB Output is correct
7 Correct 345 ms 24272 KB Output is correct
8 Correct 377 ms 24432 KB Output is correct
9 Correct 375 ms 25236 KB Output is correct
10 Correct 311 ms 25336 KB Output is correct
11 Correct 173 ms 17716 KB Output is correct
12 Correct 378 ms 25120 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 401 ms 24508 KB Output is correct
2 Correct 376 ms 24324 KB Output is correct
3 Correct 391 ms 24308 KB Output is correct
4 Correct 417 ms 24264 KB Output is correct
5 Correct 390 ms 24284 KB Output is correct
6 Correct 406 ms 24536 KB Output is correct
7 Correct 396 ms 24260 KB Output is correct
8 Correct 413 ms 24516 KB Output is correct
9 Correct 376 ms 24260 KB Output is correct
10 Correct 375 ms 24364 KB Output is correct
11 Correct 139 ms 17844 KB Output is correct
12 Correct 381 ms 24620 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 2072 KB Output is correct
2 Correct 1 ms 332 KB Output is correct
3 Correct 1 ms 332 KB Output is correct
4 Correct 18 ms 3660 KB Output is correct
5 Correct 9 ms 2040 KB Output is correct
6 Correct 1 ms 460 KB Output is correct
7 Correct 2 ms 460 KB Output is correct
8 Correct 2 ms 588 KB Output is correct
9 Correct 1 ms 460 KB Output is correct
10 Correct 9 ms 1996 KB Output is correct
11 Correct 1 ms 332 KB Output is correct
12 Correct 1 ms 332 KB Output is correct
13 Correct 1 ms 332 KB Output is correct
14 Correct 1 ms 348 KB Output is correct
15 Correct 1 ms 332 KB Output is correct

Subtask #4
45.0 / 45.0

# Verdict Execution time Memory Grader output
1 Correct 369 ms 25340 KB Output is correct
2 Correct 346 ms 24288 KB Output is correct
3 Correct 356 ms 25084 KB Output is correct
4 Correct 342 ms 25168 KB Output is correct
5 Correct 399 ms 24276 KB Output is correct
6 Correct 370 ms 25244 KB Output is correct
7 Correct 345 ms 24272 KB Output is correct
8 Correct 377 ms 24432 KB Output is correct
9 Correct 375 ms 25236 KB Output is correct
10 Correct 311 ms 25336 KB Output is correct
11 Correct 173 ms 17716 KB Output is correct
12 Correct 378 ms 25120 KB Output is correct
13 Correct 401 ms 24508 KB Output is correct
14 Correct 376 ms 24324 KB Output is correct
15 Correct 391 ms 24308 KB Output is correct
16 Correct 417 ms 24264 KB Output is correct
17 Correct 390 ms 24284 KB Output is correct
18 Correct 406 ms 24536 KB Output is correct
19 Correct 396 ms 24260 KB Output is correct
20 Correct 413 ms 24516 KB Output is correct
21 Correct 376 ms 24260 KB Output is correct
22 Correct 375 ms 24364 KB Output is correct
23 Correct 139 ms 17844 KB Output is correct
24 Correct 381 ms 24620 KB Output is correct
25 Correct 9 ms 2072 KB Output is correct
26 Correct 1 ms 332 KB Output is correct
27 Correct 1 ms 332 KB Output is correct
28 Correct 18 ms 3660 KB Output is correct
29 Correct 9 ms 2040 KB Output is correct
30 Correct 1 ms 460 KB Output is correct
31 Correct 2 ms 460 KB Output is correct
32 Correct 2 ms 588 KB Output is correct
33 Correct 1 ms 460 KB Output is correct
34 Correct 9 ms 1996 KB Output is correct
35 Correct 1 ms 332 KB Output is correct
36 Correct 1 ms 332 KB Output is correct
37 Correct 1 ms 332 KB Output is correct
38 Correct 1 ms 348 KB Output is correct
39 Correct 1 ms 332 KB Output is correct
40 Correct 400 ms 24788 KB Output is correct
41 Correct 364 ms 24996 KB Output is correct
42 Correct 395 ms 25084 KB Output is correct
43 Correct 140 ms 17844 KB Output is correct
44 Correct 156 ms 17788 KB Output is correct
45 Correct 351 ms 24348 KB Output is correct
46 Correct 318 ms 23948 KB Output is correct
47 Correct 368 ms 25084 KB Output is correct
48 Correct 156 ms 17288 KB Output is correct
49 Correct 297 ms 24192 KB Output is correct
50 Correct 348 ms 24712 KB Output is correct
51 Correct 341 ms 24228 KB Output is correct