제출 #714548

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
714548		tcmmichaelb139	Commuter Pass (JOI18_commuter_pass)	C++17	0 / 100	424 ms	26456 KiB

commuter_pass

#include "bits/stdc++.h"
using namespace std;

struct node {
    int v;
    long long time;
    int prev;

    bool operator<(const node &rhs) const {
        return time > rhs.time;
    }
};

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    int N, M, S, T, U, V;
    cin >> N >> M >> S >> T >> U >> V;
    vector<pair<int, long long>> adj[N + 1];
    for (int i = 0; i < M; i++) {
        int a, b, c;
        cin >> a >> b >> c;
        adj[a].push_back({b, c});
        adj[b].push_back({a, c});
    }

    auto distcalc = [&](int s) {
        priority_queue<pair<long long, int>, vector<pair<long long, int>>, greater<pair<long long, int>>> q;
        vector<long long> dist(N + 1, 1e18);
        vector<bool> vis(N + 1);

        q.push({0, s});
        while (!q.empty()) {
            pair<long long, int> v = q.top();
            q.pop();

            if (vis[v.second]) continue;
            vis[v.second] = true;

            dist[v.second] = v.first;

            for (auto u : adj[v.second]) {
                q.push({u.second + v.first, u.first});
            }
        }

        return dist;
    };

    vector<long long> fu = distcalc(U), fv = distcalc(V);

    priority_queue<node> q;
    vector<bool> vis(N + 1);
    vector<long long> mtu(N + 1, 1e18), mtv(N + 1, 1e18);

    q.push({S, 0, S});

    long long bt = -1, ans = 1e18;

    while (!q.empty()) {
        node v = q.top();
        q.pop();

        if (vis[v.v]) {
            if (min(mtu[v.prev], fu[v.v]) + min(mtv[v.prev], fv[v.v]) < mtu[v.v] + mtv[v.v]) {
                mtu[v.v] = min(fu[v.v], mtu[v.prev]);
                mtv[v.v] = min(fv[v.v], mtv[v.prev]);
            }
            continue;
        }
        vis[v.v] = true;

        mtu[v.v] = min(fu[v.v], mtu[v.prev]);
        mtv[v.v] = min(fv[v.v], mtv[v.prev]);

        for (auto u : adj[v.v]) {
            q.push({u.first, v.time + u.second, v.v});
        }
    }
    cout << min(mtu[T] + mtv[T], fu[V]) << '\n';
}

컴파일 시 표준 에러 (stderr) 메시지

commuter_pass.cpp: In function 'int main()':
commuter_pass.cpp:59:15: warning: unused variable 'bt' [-Wunused-variable]
   59 |     long long bt = -1, ans = 1e18;
      |               ^~
commuter_pass.cpp:59:24: warning: unused variable 'ans' [-Wunused-variable]
   59 |     long long bt = -1, ans = 1e18;
      |                        ^~~

• Subtask 1: 0 / 16
• Subtask 2: 0 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45