Submission #1056490

#	Time	Username	Problem	Language	Result	Execution time	Memory
1056490		alexdd	Cyberland (APIO23_cyberland)	C++17	100 / 100	2956 ms	127648 KiB

cyberland

#include "cyberland.h"
#include <bits/stdc++.h>
using namespace std;
typedef double ld;
const long long INF = 1e18;
const int MAXK = 67;
vector<pair<int,int>> con[100005];
vector<int> tip;
ld dist[MAXK+1][100005];

bool visited[100005];
void dfs(int nod, int H)
{
    visited[nod]=1;
    for(auto [adj,c]:con[nod])
        if(!visited[adj] && adj!=H)
            dfs(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) {
    K = min(K, MAXK);
    for(int i=0;i<N;i++)
    {
        con[i].clear();
        visited[i]=0;
    }
    tip = arr;
    for(int i=0;i<M;i++)
    {
        con[x[i]].push_back({y[i],c[i]});
        con[y[i]].push_back({x[i],c[i]});
    }
    dfs(0,H);
    for(int nr=0;nr<=K;nr++)
        for(int i=0;i<N;i++)
            dist[nr][i]=INF;
    priority_queue<pair<ld,pair<int,int>>> pq;
    for(int i=0;i<N;i++)
    {
        if(i==0 || (visited[i] && tip[i]==0))
        {
            pq.push({0,{0,i}});
            dist[0][i]=0;
        }
    }
    while(!pq.empty())
    {
        ld cdist = -pq.top().first;
        int nod = pq.top().second.second;
        int cnt = pq.top().second.first;
        pq.pop();
        if(cdist!=dist[cnt][nod])
            continue;
        for(auto [adj,c]:con[nod])
        {
            if(adj==H)
            {
                if(tip[adj]==0)
                    dist[0][adj]=0;
                else if(tip[adj]==2)
                    dist[0][adj]=min(dist[0][adj], (cdist+(ld)c)/2);
                else
                    dist[0][adj]=min(dist[0][adj], cdist+c);
            }
            else if(tip[adj]==2)
            {
                if(dist[cnt][adj] > cdist + c)
                {
                    dist[cnt][adj] = cdist + c;
                    pq.push({-dist[cnt][adj],{cnt,adj}});
                }
                if(cnt+1<=K && dist[cnt+1][adj] > (cdist + (ld)c)/2)
                {
                    dist[cnt+1][adj] = (cdist + (ld)c)/2;
                    pq.push({-dist[cnt+1][adj],{cnt+1,adj}});
                }
            }
            else if(tip[adj]==1)
            {
                if(dist[cnt][adj] > cdist + c)
                {
                    dist[cnt][adj] = cdist + c;
                    pq.push({-dist[cnt][adj],{cnt,adj}});
                }
            }
        }
    }
    ld mnm=INF;
    for(int cnt=0;cnt<=K;cnt++)
        mnm = min(mnm, dist[cnt][H]);
    if(mnm==INF)
        return -1;
    else
        return mnm;
}

• 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