Submission #981919

#	Time	Username	Problem	Language	Result	Execution time	Memory
981919		8pete8	Cyberland (APIO23_cyberland)	C++17	97 / 100	3074 ms	93600 KiB

cyberland

#include "cyberland.h"
#include<iostream>
#include<vector>
#include<queue>
using namespace std;
#define ll long long
#define pb push_back
#define pii pair<int,int>
#define s second
#define f first
using namespace std;
//#define int long long
//#define double long double
const ll inf=1e18,mxn=1e5;
double pre=1e-7;
struct info{
    double cost;
    int cur,use;
    bool operator<(info a)const{return (cost>a.cost);};
};
vector<int>p(mxn+10);
priority_queue<info>pq;
int cur,use;
double cost,ans;
int find(int u){return (p[u]==u)?u:p[u]=find(p[u]);}
double solve(int n,int m,int k,int H,vector<int>x,vector<int>y,vector<int>c,vector<int> arr){
    k=min(k,69);
    for(int i=0;i<n;i++)p[i]=i;
    vector<vector<double>>what(n+1,vector<double>(k+1,inf));
    vector<vector<pii>>adj(n+1);
    for(int i=0;i<m;i++){
        adj[x[i]].pb({y[i],c[i]});
        adj[y[i]].pb({x[i],c[i]});
        p[find(x[i])]=find(y[i]);
    }
    adj[H].clear();
    for(int i=0;i<n;i++)if(arr[i]==0&&find(0)==find(i))pq.push({0,i,0});
    what[0][0]=0;
    pq.push({0,0,0});
    ans=inf;
    while(!pq.empty()){
        cur=pq.top().cur,use=pq.top().use,cost=pq.top().cost;
        pq.pop();
        if(what[cur][use]<cost)continue;
        if(cur==H)ans=min(ans,cost);
        for(auto i:adj[cur]){
            if(what[cur][use]+i.s<what[i.f][use]){
                what[i.f][use]=cost+i.s;
                if(arr[i.f]==0)what[i.f][use]=0;
                pq.push((info){what[i.f][use]*1.0,i.f,use});
            }
            if(arr[cur]==2&&use<k){
                if(what[i.f][use+1]>(cost*1.0)/2+i.s){
                    what[i.f][use+1]=(cost*1.0)/2+i.s;
                    pq.push((info){what[i.f][use+1],i.f,use+1});
                }
            }
        }
    }
    for(int i=0;i<n;i++)adj[i].clear();
    if(ans==inf)return -1;
    return ans;
}
#undef int
/*
int32_t main(){
    int t;cin>>t;
    int n,m,k,h;cin>>n>>m>>k>>h;
    vector<int>x(m),y(m),z(m),arr(n);
    for(int i=0;i<n;i++)cin>>arr[i];
    for(int i=0;i<m;i++)cin>>x[i]>>y[i]>>z[i];
    cout<<solve(n,m,k,h,x,y,z,arr);
}*/
/*
1
4 4 30
3
1 1 2 1
0 1 5
0 2 4
1 3 2
2 3 4
*/

• 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: 0 / 3