Submission #870027

#	Time	Username	Problem	Language	Result	Execution time	Memory
870027		Pannda	Robot (JOI21_ho_t4)	C++17	0 / 100	36 ms	6432 KiB

Main

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

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    int n, m;
    cin >> n >> m;
    vector<vector<array<int, 3>>> adj(n);

    for (int i = 0; i < m; i++) {
        int u, v, color, cost;
        cin >> u >> v >> color >> cost;
        u--;
        v--;
        adj[u].push_back({ v, color, cost });
        adj[v].push_back({ u, color, cost });
    }

    vector<long long> dist(n, -1);
    priority_queue<array<long long, 3>, vector<array<long long, 3>>, greater<>> pq;
    dist[0] = 0;
    pq.push({0, 0, -1});

    while (!pq.empty()) {
        auto [d, u, p] = pq.top();
        pq.pop();
        if (dist[u] != d) continue;
        map<int, long long> mp; // color to sum of cost
        for (auto [v, color, cost] : adj[u]) {
            if (v == p) {
                continue;
            }
            mp[color] += cost;
        }
        for (auto [v, color, cost] : adj[u]) {
            if (v == p) {
                continue;
            }
            long long w = min(1LL * cost, mp[color] - cost);
            if (dist[v] == -1 || dist[u] + w < dist[v]) {
                dist[v] = dist[u] + w;
                pq.push({dist[v], v, u});
            }
        }
    }

    cout << dist[n - 1] << '\n';
}

• Subtask 1: 0 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42