Cod sursa(job #2043824)

Utilizator GeorgeCalinPetruta George-Calin GeorgeCalin Data 20 octombrie 2017 16:52:19
Problema Arbori de intervale Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 1.27 kb
#include <fstream>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");

int arb[4000003];
int x,n,m,poz,maxim,sfarsit,inceput,a,b,valoare,mij;

void actualizare(int nod,int st,int dr)
{
    if(st==dr)
    {
        arb[nod]=valoare;
        return;
    }
    mij=(st+dr)/2;
    if(poz<=mij)
        actualizare(2*nod,st,mij);
    else
        actualizare(2*nod+1,mij+1,dr);

    arb[nod]=max(arb[2*nod],arb[2*nod+1]);
}

void interogare(int nod,int st,int dr)
{
    if(st>=inceput&&dr<=sfarsit)
    {
        if(arb[nod]>maxim)
        {
            maxim=arb[nod];
        }
        return;
    }
    mij=(st+dr)/2;
    if(mij<sfarsit)interogare(2*nod+1,mij+1,dr);
    if(inceput<=mij)interogare(2*nod,st,mij);

}

int main()
{
    fin>>n>>m;
    for(int i=1;i<=n;i++)
    {
        fin>>x;
        valoare=x;
        poz=i;
        actualizare(1,1,n);
    }
    for(int i=1;i<=m;i++)
    {
        fin>>x>>a>>b;
        if(x==0)
        {
            maxim=-1;
            sfarsit=b;
            inceput=a;
            interogare(1,1,n);
            fout<<maxim<<"\n";
        }
        else
        {
            poz=a;
            valoare=b;
            actualizare(1,1,n);
        }
    }
    return 0;
}