Submission #983201

#	Time	Username	Problem	Language	Result	Execution time	Memory
983201		vjudge1	Cyberland (APIO23_cyberland)	C++17	15 / 100	1975 ms	2880 KiB

cyberland

#include <vector>
#include <queue>
#include <limits>

using namespace std;

double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr) {
    vector<double> distances(N, numeric_limits<double>::infinity());
    distances[0] = 0;

    // Priority queue to store (distance, node)
    priority_queue<pair<double, int>, vector<pair<double, int>>, greater<pair<double, int>>> pq;
    pq.push({0, 0});

    // Main Dijkstra's algorithm loop
    while (!pq.empty()) {
        double dist = pq.top().first;
        int node = pq.top().second;
        pq.pop();

        // Check if we've reached Cyberland
        if (node == H) {
            return dist;
        }

        // Check if the current node has the divide-by-2 ability
        if (arr[node] == 2 && K > 0) {
            // Consider using the divide-by-2 ability
            double new_dist = dist / 2.0;
            // If using the ability leads to a shorter path, update distance
            if (new_dist < distances[node]) {
                distances[node] = new_dist;
                // Push the updated distance to the priority queue
                pq.push({new_dist, node});
                // Decrement the remaining uses of divide-by-2 ability
                K--;
            }
        }

        // Iterate through neighbors of the current node
        for (int i = 0; i < M; i++) {
            int neighbor;
            if (x[i] == node) {
                neighbor = y[i];
            } else if (y[i] == node) {
                neighbor = x[i];
            } else {
                continue;
            }

            // Calculate the new distance to the neighbor
            double new_dist = dist + c[i];

            // Update the distance if it's shorter
            if (new_dist < distances[neighbor]) {
                distances[neighbor] = new_dist;
                pq.push({new_dist, neighbor});
            }
        }
    }

    // If Cyberland is not reachable
    return -1;
}

• Subtask 1: 0 / 5
• Subtask 2: 8 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 19
• Subtask 5: 7 / 7
• Subtask 6: 0 / 16
• Subtask 7: 0 / 29
• Subtask 8: 0 / 3