Submission #1178919

#	Time	Username	Problem	Language	Result	Execution time	Memory
1178919		Gurban	Cyberland (APIO23_cyberland)	C++17	44 / 100	3094 ms	10484 KiB

cyberland

#include "cyberland.h"
#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;

const double inf = 2e14;
const int maxn=1e5+5;
int h;
vector<pair<int,double>>E[maxn];

vector<double>Dijkstra(int n,vector<int>s, vector<double>ds){
    
    priority_queue<pair<double,int>>p;
    vector<bool>vis(n,0);
    
    for(auto i : s){
        p.push({-ds[i], i});
    }
    while(!p.empty()){
        int x = p.top().second;
        p.pop();
        if(vis[x]) continue;
        vis[x] = 1;
        if(x == h) continue; 
        for(auto i : E[x]){
            int to = i.first;
            double w = i.second;
            if(ds[to] > ds[x] + w){
                ds[to] = ds[x] + w;
                p.push({-ds[to], to});
            }
        }
    }
    return ds;
}

double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr) {
    h = H;
    vector<int>twos;
    for(int i = 0;i < N;i++){
        E[i].clear();
        if(arr[i] == 2) twos.push_back(i);
    }
    for(int i = 0;i < M;i++){
        E[x[i]].push_back({y[i],c[i]});
        E[y[i]].push_back({x[i],c[i]});
    }
    vector<int>now;
    now.push_back(0);

    vector<double>dis(N,inf);
    dis[0] = 0;

    dis = Dijkstra(N, now, dis);

    dis[0] = 0;
    for(int i = 1;i < N;i++){
        if(arr[i] == 0 and dis[i] < inf-2){
            now.push_back(i);
            dis[i] = 0;
        }
        else dis[i] = inf;
    }

    double ans = inf;
    for(int i = 1;i <= K;i++){
        dis = Dijkstra(N, now, dis);
        ans = min(ans, dis[H]);
        if(arr[H] == 2) ans = min(ans, dis[H] / 2);
        vector<double>ndis(N,inf);
        for(auto t : twos){
            if(t == H) continue;
            double nw = dis[t] / 2;
            for(auto j : E[t]){
                int to = j.first;
                double w = j.second;
                ndis[to] = min(ndis[to],nw + w);
            }
        }
        vector<int>ns;
        for(int j = 0;j < N;j++){
            if(ndis[j] < inf-2){
                ns.push_back(j);
            }
        }
        now = ns;
        dis = ndis;
    }
    dis = Dijkstra(N, now, dis);
    ans = min(ans, dis[H]);

    if(ans >= inf-2) ans = -1;

    return ans;
}

• 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