Submission #708634

#	Time	Username	Problem	Language	Result	Execution time	Memory
708634		ToroTN	Factories (JOI14_factories)	C++14	15 / 100	3322 ms	206800 KiB

factories

#include "factories.h"
#include<bits/stdc++.h>
using namespace std;
//#include "grader.cpp"
#define ll long long
#define pb push_back
#define X first
#define Y second
vector<pair<ll,ll> > v[500005];
ll n,lv[500005],dis[500005][25],par[200005][25];
void dfs(ll u,ll p)
{
    for(int i=0;i<v[u].size();i++)
    {
        ll node=v[u][i].X,cost=v[u][i].Y;
        if(node==p)continue;
        lv[node]=lv[u]+1;
        dis[node][0]=cost;
        par[node][0]=u;
        dfs(node,u);
    }
}
pair<ll,ll> lca(ll a,ll b)
{
    ll sum=0;
    if(lv[a]<lv[b])swap(a,b);
    for(int i=20;i>=0;i--)
    {
        if(lv[par[a][i]]>=lv[b])
        {
            sum+=dis[a][i],a=par[a][i];
        }
    }
    if(a==b)return {a,sum};
    for(int i=20;i>=0;i--)
    {
        if(par[a][i]!=par[b][i])
        {
            sum+=dis[a][i],sum+=dis[b][i];
            a=par[a][i],b=par[b][i];
        }
    }
    sum+=dis[a][0],sum+=dis[b][0];
    return {par[a][0],sum};
}
ll sz[500005],vis[500005],par_cen[500005];
ll dfs_sz(ll u,ll p)
{
    sz[u]=1;
    for(int i=0;i<v[u].size();i++)
    {
        ll node=v[u][i].X;
        if(node==p||vis[node])continue;
        sz[u]+=dfs_sz(node,u);
    }
    return sz[u];
}
ll find_cen(ll u,ll p,ll size)
{
    for(int i=0;i<v[u].size();i++)
    {
        ll node=v[u][i].X;
        if(node==p||vis[node])continue;
        if(sz[node]>size/2)return find_cen(node,u,size);
    }
    return u;
}
void centroid(ll u,ll p)
{
    dfs_sz(u,u);
    ll cen=find_cen(u,u,sz[u]);
    vis[cen]=1;
    par_cen[cen]=p;
    for(int i=0;i<v[cen].size();i++)
    {
        ll node=v[cen][i].X;
        if(node==p||vis[node])continue;
        centroid(node,cen);
    }
}
ll mn[500005];
void Init(int N, int A[], int B[], int D[]) 
{
    n=N;
    for(int i=0;i<n-1;i++)
    {
        v[A[i]+1].pb({B[i]+1,D[i]});
        v[B[i]+1].pb({A[i]+1,D[i]});
    }
    par[1][0]=1;
    dfs(1,1);
    for(int i=1;i<=20;i++)
    {
        for(int j=1;j<=n;j++)
        {
            dis[j][i]=dis[j][i-1]+dis[par[j][i-1]][i-1];
            par[j][i]=par[par[j][i-1]][i-1];
        }
    }
    dfs_sz(1,1);
    centroid(1,0);
    for(int i=1;i<=n;i++)mn[i]=1e18;
}
void update(ll num,ll type)
{
    ll u=num;
    while(1)
    {
        if(type==0)
        {
            mn[u]=min(mn[u],lca(u,num).Y);
        }else
        {
            mn[u]=1e18;
        }
        u=par_cen[u];
        if(u==0)break;
    }
}
ll query(ll num)
{
    ll u=num,val=1e18;
    while(1)
    {
        val=min(val,lca(num,u).Y+mn[u]);
        u=par_cen[u];
        if(u==0)break;
    }
    return val;
}
long long Query(int S, int X[], int T, int Y[]) 
{
    for(int i=0;i<S;i++)
    {
        update(X[i]+1,0);
    }
    ll ans=1e18;
    for(int i=0;i<T;i++)
    {
        ans=min(ans,query(Y[i]+1));
    }
    for(int i=0;i<S;i++)
    {
        update(X[i]+1,1);
    }
    return ans;
}

Compilation message (stderr)

factories.cpp: In function 'void dfs(long long int, long long int)':
factories.cpp:13:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   13 |     for(int i=0;i<v[u].size();i++)
      |                 ~^~~~~~~~~~~~
factories.cpp: In function 'long long int dfs_sz(long long int, long long int)':
factories.cpp:50:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |     for(int i=0;i<v[u].size();i++)
      |                 ~^~~~~~~~~~~~
factories.cpp: In function 'long long int find_cen(long long int, long long int, long long int)':
factories.cpp:60:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |     for(int i=0;i<v[u].size();i++)
      |                 ~^~~~~~~~~~~~
factories.cpp: In function 'void centroid(long long int, long long int)':
factories.cpp:74:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   74 |     for(int i=0;i<v[cen].size();i++)
      |                 ~^~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 0 / 18
• Subtask 3: 0 / 67