Submission #958164

#	Time	Username	Problem	Language	Result	Execution time	Memory
958164		irmuun	Factories (JOI14_factories)	C++17	100 / 100	2597 ms	122772 KiB

factories

#include<bits/stdc++.h>
#include "factories.h"
 
using namespace std;
 
#define ll long long
#define pb push_back
#define ff first
#define ss second
#define all(s) s.begin(),s.end()
#define rall(s) s.rbegin(),s.rend()
 
const int N=5e5+5;
vector<ll>dist(N);
vector<int>sz(N),heavy(N,-1),head(N),par(N);
vector<pair<int,int>>adj[N];

void dfs(int x){
    sz[x]=1;
    int mx=0;
    for(auto [y,w]:adj[x]){
        if(y!=par[x]){
            dist[y]=dist[x]+w;
            par[y]=x;
            dfs(y);
            sz[x]+=sz[y];
            if(sz[y]>mx){
                mx=sz[y];
                heavy[x]=y;
            }
        }
    }
}
void HLD(int x,int h){
    head[x]=h;
    if(heavy[x]>-1){
        HLD(heavy[x],h);
    }
    for(auto [y,w]:adj[x]){
        if(y!=par[x]&&y!=heavy[x]){
            HLD(y,y);
        }
    }
}
 
void Init(int n,int a[],int b[],int d[]){
    for(int i=0;i<n-1;i++){
        adj[a[i]].pb({b[i],d[i]});
        adj[b[i]].pb({a[i],d[i]});
    }
    par[0]=-1;
    dfs(0);
    HLD(0,0);
}
 
ll Query(int s,int x[],int t,int y[]){
    vector<array<ll,4>>v;
    for(int i=0;i<s;i++){
        int j=x[i];
        v.pb({head[j],-dist[j],x[i],0});
        j=head[j];
        while(j>0){
            j=par[j];
            v.pb({head[j],-dist[j],x[i],0});
            j=head[j];
        }
    }
    for(int i=0;i<t;i++){
        int j=y[i];
        v.pb({head[j],-dist[j],y[i],1});
        j=head[j];
        while(j>0){
            j=par[j];
            v.pb({head[j],-dist[j],y[i],1});
            j=head[j];
        }
    }
    sort(all(v));
    vector<array<ll,3>>cur;
    ll ans=1e18;
    for(int i=0;i<v.size();i++){
        cur.pb({-v[i][1],v[i][2],v[i][3]});
        if(i==(int)v.size()-1||v[i][0]!=v[i+1][0]){
            ll mn0=1e18,mn1=1e18;
            for(int j=0;j<cur.size();j++){
                if(cur[j][2]==0){
                    mn0=min(mn0,dist[cur[j][1]]);
                    ans=min(ans,dist[cur[j][1]]+mn1-2*cur[j][0]);
                }
                else{
                    mn1=min(mn1,dist[cur[j][1]]);
                    ans=min(ans,dist[cur[j][1]]+mn0-2*cur[j][0]);
                }
            }
            cur.clear();
        }
    }
    return ans;
}

Compilation message (stderr)

factories.cpp: In function 'long long int Query(int, int*, int, int*)':
factories.cpp:81:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<long long int, 4> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   81 |     for(int i=0;i<v.size();i++){
      |                 ~^~~~~~~~~
factories.cpp:85:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::array<long long int, 3> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   85 |             for(int j=0;j<cur.size();j++){
      |                         ~^~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 18 / 18
• Subtask 3: 67 / 67