Cod sursa(job #2922425)

Utilizator NutaAlexandruASN49K NutaAlexandru Data 8 septembrie 2022 11:38:33
Problema Heavy Path Decomposition Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 5.01 kb
#include <fstream>
#include <vector>
#include <cmath>
#include <algorithm>
#include <set>
#include <queue>
using namespace std;
class LCA
{
    vector<vector<int>>rmq;
    vector<int>e,poz,h,lg;
    int n;
    void dfs(vector<vector<int>>&a,int nod,int tata)
    {
        h[nod]=h[tata]+1;
        poz[nod]=(int)e.size();
        e.push_back(nod);
        for(auto c:a[nod])
        {
            if(c==tata)continue;
            dfs(a,c,nod);
            e.push_back(nod);
        }
    }
    void dfs(vector<vector<int>>&a)
    {
        dfs(a,1,1);
    }
    int maxx(int x,int y)
    {
        if(h[x]>h[y])return y;
        return x;
    }
    void build_rmq()
    {
        for(int i=1;i<=n;i++)
        {
            rmq[i][0]=e[i];
        }
        for(int j=1;(1<<j)<=n;j++)
        {
            for(int i=1;i+(1<<j)-1<=n;i++)
            {
                rmq[i][j]=maxx(rmq[i][j-1],rmq[i+(1<<(j-1))][j-1]);
            }
        }
    }
public:
    LCA(vector<vector<int>>&a)
    {
        n=(int)a.size()-1;
        poz.resize(n+1);
        h.resize(n+1);
        h[1]=0;
        e={0};
        dfs(a);
        n=(int)e.size()-1;
        lg.resize(n+1);
        lg[1]=lg[0]=0;
        for(int i=2;i<=n;i++)
        {
            lg[i]=lg[i/2]+1;
        }
        rmq=vector<vector<int>>(n+1,vector<int>(lg[n]+2));
        build_rmq();
    }
    int get(int x, int y)
    {
        int l=poz[x],r=poz[y];
        if(r<l)
        {
            swap(l,r);
        }
        int lung=lg[r-l+1];
        return maxx(rmq[l][lung],rmq[r-(1<<lung)+1][lung]);
    }

};

class Seg_tree
{
    int n,minn;
    vector<int>aint;
    void build(vector<int>&a,int nod,int st,int dr)
    {
        if(st==dr)
        {
            aint[nod]=a[st];
            return;
        }
        int m=(st+dr)/2;
        build(a,2*nod,st,m);
        build(a,2*nod+1,m+1,dr);
        aint[nod]=max(aint[2*nod],aint[2*nod+1]);
    }
    void update(int nod,int st,int dr,const int& poz,const int& val)
    {
        if(st>poz || dr<poz)return;
        if(st==dr)
        {
            aint[nod]=val;
            return;
        }
        int m=(st+dr)/2;
        update(2*nod,st,m,poz,val);
        update(2*nod+1,m+1,dr,poz,val);
        aint[nod]=max(aint[2*nod],aint[2*nod+1]);
    }
    int query(int nod,int st,int dr,const int& l,const int& r)
    {
        if(st>r || dr<l)return minn;
        if(st>=l && dr<=r)
        {
            return aint[nod];
        }
        int m=(st+dr)/2;
        return max(query(2*nod,st,m,l,r),query(2*nod+1,m+1,dr,l,r));
    }
public:
    Seg_tree(vector<int>&a,int x)
    {
        n=(int)a.size()-1;
        aint.resize(4*n+1);
        build(a,1,1,n);
        minn=x;
    }
    void update(int poz,int val)
    {
        update(1,1,n,poz,val);
    }
    int query(int l,int r)
    {
        return query(1,1,n,l,r);
    }
};

class heavy
{
    vector<Seg_tree>aint;
    vector<vector<int>>a;
    const vector<int>aux={-1};
    ///dp= nr de elemente  , poz
    vector<int>dp,t;
    vector<pair<int,int>>poz;
    int n;
    void dfs1(vector<vector<int>>&g,int nod,int tata)
    {
        t[nod]=tata;
        dp[nod]=1;
        for(auto &c:g[nod])
        {
            if(c==tata)continue;
            dfs1(g,c,nod);
            dp[nod]+=dp[c];
        }
    }
    void dfs2(vector<vector<int>>&g,vector<int>&val,const int& nod,const int& tata,int lant)
    {
        if(lant==-1)
        {
            lant=(int)a.size();
            a.push_back(aux);
        }
        poz[nod].first=lant;
        poz[nod].second=(int)a[lant].size();
        a[lant].push_back(val[nod]);
        dp[0]=0;
        int maxx=0;
        for(auto &c:g[nod])
        {
            if(c==tata)continue;
            if(dp[c]>dp[maxx])
            {
                maxx=c;
            }
        }
        for(auto &c:g[nod])
        {
            if(c==tata)continue;
            if(c==maxx)
            {
                dfs2(g,val,c,nod,lant);
            }
            else
            {
                dfs2(g,val,c,nod,-1);
            }
        }
    }
    void dfs(vector<vector<int>>&g,vector<int>val)
    {
        dfs1(g,1,0);
        dfs2(g,val,1,0,-1);
    }
public:
    heavy(vector<vector<int>>&g,vector<int>&val)
    {
        LCA lca(g);
        n=(int)g.size()-1;
        poz.resize(n+1);
        dp.resize(n+1);
        t.resize(n+1);
        dfs(g,val);
    }
    void print(){
        for(int i=1;i<=n;i++)
        {
            cout<<poz[i].first<<' '<<poz[i].second<<'\n';
        }
    }


};
int main()
{
    ifstream cin("heavypath.in");
    ofstream cout("heavypath.out");
    int n,q;
    cin>>n>>q;
    vector<int>val(n+1,0);
    vector<vector<int>>a(n+1);
    for(int i=1;i<=n;i++)cin>>val[i];
    for(int i=1;i<n;i++)
    {
        int x,y;
        cin>>x>>y;
        a[x].push_back(y);
        a[y].push_back(x);
    }
    heavy tree(a,val);
    tree.print();
}