Submission #1309365

#	Time	Username	Problem	Language	Result	Execution time	Memory
1309365		azamurai	Cyberland (APIO23_cyberland)	C++20	15 / 100	974 ms	2162688 KiB

cyberland

#include <bits/stdc++.h>
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
) {
    const double INF = 1e18;

    // строим граф
    vector<vector<pair<int,double>>> g(N);
    for (int i = 0; i < M; i++) {
        g[x[i]].push_back({y[i], c[i]});
        g[y[i]].push_back({x[i], c[i]});
    }

    // dp[k][v] = минимальное время в v, использовав k делений
    vector<vector<double>> dp(K + 1, vector<double>(N, INF));

    priority_queue<
        pair<double, pair<int,int>>,
        vector<pair<double, pair<int,int>>>,
        greater<>
    > pq;

    dp[0][0] = 0;
    pq.push({0, {0, 0}});

    while (!pq.empty()) {
        auto [dist, st] = pq.top();
        pq.pop();

        int v = st.first;
        int used = st.second;

        if (dp[used][v] != dist) continue;

        for (auto [u, w] : g[v]) {
            double base = dist + w;

            // 1) ничего не делать
            if (dp[used][u] > base) {
                dp[used][u] = base;
                pq.push({base, {u, used}});
            }

            // 2) обнуление (если arr[u] == 0)
            if (arr[u] == 0) {
                if (dp[used][u] > 0) {
                    dp[used][u] = 0;
                    pq.push({0, {u, used}});
                }
            }

            // 3) деление на 2 (если arr[u] == 2)
            if (arr[u] == 2 && used < K) {
                double half = base * 0.5;
                if (dp[used + 1][u] > half) {
                    dp[used + 1][u] = half;
                    pq.push({half, {u, used + 1}});
                }
            }
        }
    }

    double ans = INF;
    for (int i = 0; i <= K; i++) {
        ans = min(ans, dp[i][H]);
    }

    if (ans >= INF / 2) return -1;
    return ans;
}

• 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