Submission #1154268

#	Time	Username	Problem	Language	Result	Execution time	Memory
1154268		burgerguy	Cyberland (APIO23_cyberland)	C++20	0 / 100	36 ms	27720 KiB

cyberland

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

vector<bool> isReachable;

void dfs(ll v, vector<vector<pair<ll,double>>>& adj, ll H) {
    if(v == H) return;

    for(pair<ll,ll> u : adj[v]) {
        if(!isReachable[u.first]) {
            isReachable[u.first] = true;
            dfs(u.first, adj, H);
        }
    }
}

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) {
    vector<vector<pair<ll,double>>> adj(N);
    for (int i = 0; i < M; i++) {
        adj[x[i]].emplace_back(y[i], c[i]);
        adj[y[i]].emplace_back(x[i], c[i]);
    }

    isReachable.clear();
    isReachable.resize(N);

    dfs(0, adj, H);
    isReachable[0] = true;

    if(!isReachable[H]) return -1;

    K = min(K, 100);

    priority_queue<tuple<double,ll,ll>, vector<tuple<double,ll,ll>>, greater<>> pq;
    vector<vector<double>> dist(N + 10, vector<double>(K + 10, 1e18));
    vector<double> divBy = {1};
    for(int i = 0; i < K + 10; i++) {
        divBy.push_back(divBy[i]/2);
    }

    pq.emplace(K, H, 0);

    while(!pq.empty()) {
        double curDistance = get<0>(pq.top());
        ll curNode = get<1>(pq.top());
        ll curK = get<2>(pq.top());

        pq.pop();

        if(curDistance > dist[curNode][curK]) continue;

        if(curNode == 0 || arr[curNode] == 0) return curDistance;

        for(auto u : adj[curNode]) {
            if(isReachable[u.first]) {
                double newDistance = curDistance + u.second * divBy[K - curK];

                if(newDistance < dist[u.first][curK]) {
                    dist[u.first][curK] = newDistance;
                    pq.emplace(newDistance, u.first, curK);
                }

                if(arr[u.first] == 2 && curK > 0) {
                    double betterDistance = curDistance + u.second * divBy[K - curK + 1];

                    if(betterDistance < dist[u.first][curK + 1]) {
                        dist[u.first][curK + 1] = betterDistance;
                        pq.emplace(betterDistance, u.first, curK - 1);
                    }
                }
            }
        }
    }

    return -1;
}

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