Submission #1183672

#	Time	Username	Problem	Language	Result	Execution time	Memory
1183672		meicris	Toll (BOI17_toll)	C++17	0 / 100	269 ms	589824 KiB

toll

#include <iostream>
#include <vector>
#include <queue>
#include <unordered_map>
#include <climits>
using namespace std;
const int INF = 1e9;
int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int K, N, M, O;
    cin >> K >> N >> M >> O;
    vector<vector<pair<int, int>>> graph(N);
    for (int i = 0; i < M; ++i) {
        int a, b, c;
        cin >> a >> b >> c;
        if (b / K == a / K + 1) {
            graph[a].emplace_back(b, c);
        }
    }
    vector<vector<int>> dist(N, vector<int>(N, INF));
    auto dijkstra = [&](int start) {
        vector<int> local_dist(N, INF);
        priority_queue<pair<int, int>, vector<pair<int, int>>, greater<>> pq;
        local_dist[start] = 0;
        pq.emplace(0, start);
        while (!pq.empty()) {
            auto [d, u] = pq.top();
            pq.pop();
            if (d > local_dist[u]) continue;
            for (auto &[v, cost] : graph[u]) {
                if (local_dist[v] > local_dist[u] + cost) {
                    local_dist[v] = local_dist[u] + cost;
                    pq.emplace(local_dist[v], v);
                }
            }
        }
        dist[start] = local_dist;
    };
    for (int i = 0; i < N; ++i) {
        dijkstra(i);
    }
    for (int i = 0; i < O; ++i) {
        int a, b;
        cin >> a >> b;
        if (dist[a][b] == INF) {
            cout << -1 << '\n';
        } else {
            cout << dist[a][b] << '\n';
        }
    }
    return 0;
}

• Subtask 1: 0 / 7
• Subtask 2: 0 / 10
• Subtask 3: 0 / 8
• Subtask 4: 0 / 31
• Subtask 5: 0 / 44