Submission #1030863

#	Time	Username	Problem	Language	Result	Execution time	Memory
1030863		amine_aroua	Cyberland (APIO23_cyberland)	C++17	100 / 100	129 ms	74848 KiB

cyberland

#include "cyberland.h"

#include <bits/stdc++.h>
using namespace std;
void dfs(int x , vector<bool>&reach , vector<vector<pair<int ,int>>> &adj , int H)
{
    if(x == H || reach[x])
        return ;
    reach[x] = 1;
    for(auto [u , cost] : adj[x])
    {
        dfs(u , reach , adj , H);
    }    
}
using Node = tuple<double , int , int>;
priority_queue<Node , vector<Node> , greater<Node>> pq;
void upd(int x , int k , double d , vector<vector<double>> &dist)
{
    if(dist[x][k] > d)
    {
        dist[x][k] = d;
        pq.push({d , x , k});
    }
}
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) 
{
    pq = priority_queue<Node , vector<Node> , greater<Node>> ();
    K = min(K , 70);
    vector<vector<pair<int , int>>> adj(N);
    vector<bool> reach(N);
    vector<double> pwr(K + 1);
    pwr[0] = 1;
    for(int i = 1 ; i <= K ; i++)
    {
        pwr[i] = pwr[i - 1]/2.0;
    } 
    for(int i = 0 ; i < M ; i++)
    {
        adj[x[i]].push_back({y[i] , c[i]});
        adj[y[i]].push_back({x[i] , c[i]});
    }
    vector<vector<double>> dist(N , vector<double>(K + 1 , 1e18));
    arr[0] = 0;
    upd(H , 0 , 0 , dist);
    dfs(0 , reach ,adj ,H);
    while(!pq.empty())
    {
        auto [d , x , k] = pq.top();
        pq.pop();
        if(arr[x] == 0)
        {
            return d;
        }
        for(auto [u , cost] : adj[x])
        {
            if(!reach[u])
                continue;
            upd(u , k , cost*pwr[k] + d , dist);
            if(arr[x] == 2 && k < K)
            {
                int p = k + 1;
                upd(u , p , cost*pwr[p] + d , dist);
            }
        }
    }
    return -1;
}

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