Submission #1228198

#	Time	Username	Problem	Language	Result	Execution time	Memory
1228198		goduadzesaba	Cyberland (APIO23_cyberland)	C++20	15 / 100	1504 ms	2162688 KiB

cyberland

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

const double INF = 1e18;

double solve(int N, int M, int K, int H,
             vector<int> x, vector<int> y, vector<int> c,
             vector<int> arr) {
    
    vector<vector<pair<int, int>>> graph(N);
    for (int i = 0; i < M; ++i) {
        graph[x[i]].emplace_back(y[i], c[i]);
        graph[y[i]].emplace_back(x[i], c[i]);
    }

    // Dijkstra with state: (cost, node, divide_count)
    vector<vector<double>> dist(N, vector<double>(K + 1, INF));
    set<tuple<double, int, int>> pq;

    dist[0][0] = 0;
    pq.emplace(0.0, 0, 0);

    while (!pq.empty()) {
        auto [cost, node, divs_used] = *pq.begin();
        pq.erase(pq.begin());

        // Apply zeroing ability at the current node
        if (arr[node] == 0 && cost > 0 && dist[node][divs_used] > 0) {
            dist[node][divs_used] = 0;
            pq.emplace(0.0, node, divs_used);
            //continue;  // restart from zeroed state
        }

        // Apply divide-by-2 ability at the current node
        if (arr[node] == 2 && divs_used < K) {
            double divided_cost = cost / 2.0;
            if (dist[node][divs_used + 1] > divided_cost) {
                dist[node][divs_used + 1] = divided_cost;
                pq.emplace(divided_cost, node, divs_used + 1);
            }
        }

        // Traverse neighbors
        for (auto [to, weight] : graph[node]) {
            double new_cost = cost + weight;
            if (dist[to][divs_used] > new_cost) {
                dist[to][divs_used] = new_cost;
                pq.emplace(new_cost, to, divs_used);
            }
        }
    }

    double result = *min_element(dist[H].begin(), dist[H].end());
    return result == INF ? -1 : result;
}

• 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