Submission #769714

#	Time	Username	Problem	Language	Result	Execution time	Memory
769714		Plurm	Cyberland (APIO23_cyberland)	C++17	44 / 100	3064 ms	138308 KiB

cyberland

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

vector<pair<int, int>> g[100005];
bool reach[100005];
void dfsreach(int u, int H) {
    if (reach[u])
        return;
    reach[u] = true;
    if (u == H)
        return;
    for (auto v : g[u]) {
        dfsreach(v.first, H);
    }
}
long double dist[100005][32];
double solve(int N, int M, int K, int H, std::vector<int> x, std::vector<int> y,
             std::vector<int> c, std::vector<int> arr) {
    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]});
    }
    dfsreach(0, H);
    if (!reach[H]) {
        for (int i = 0; i < N; i++) {
            g[i].clear();
            reach[i] = false;
        }
        return -1;
    }
    priority_queue<pair<long double, int>> pq;
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < K; j++)
            dist[i][j] = 2e18;
        if (arr[i] == 0 && reach[i]) {
            pq.push({0, i});
            dist[i][0] = 0;
        }
    }
    pq.push({0, 0});
    dist[0][0] = 0;
    while (!pq.empty()) {
        auto cur = pq.top();
        pq.pop();
        for (auto nxt : g[cur.second]) {
            for (int j = 0; j < K; j++) {
                if (arr[nxt.first] == 2) {
                    if (dist[nxt.first][j + 1] >
                        (-cur.first + nxt.second) * 0.5L) {
                        dist[nxt.first][j + 1] =
                            (-cur.first + nxt.second) * 0.5L;
                        pq.push({-dist[nxt.first][j + 1], nxt.first});
                    }
                }
                if (dist[nxt.first][j] > -cur.first + nxt.second) {
                    dist[nxt.first][j] = -cur.first + nxt.second;
                    pq.push({-dist[nxt.first][j], nxt.first});
                }
            }
        }
    }
    for (int i = 0; i < N; i++) {
        g[i].clear();
        reach[i] = false;
    }
    long double mn = 2e18;
    for (int j = 0; j < K; j++) {
        mn = min(mn, dist[H][j]);
    }
    if (mn > 1e18)
        return -1;
    else
        return mn;
}

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