Cod sursa(job #1020103)

Utilizator MarghescuGabriel Marghescu Marghescu Data 1 noiembrie 2013 18:15:57
Problema Arbori de intervale Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.38 kb
#include<fstream>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int n,m;
int arb[100002];
void inserare(int nod,int st,int dr,int poz,int v)
{
    if(st==dr)
    {
        arb[nod]=v;
    }
    else
    {
        int mij=(st+dr)/2;
        if(poz<=mij)
            inserare(2*nod,st,mij,poz,v);
        else
            inserare(2*nod+1,mij+1,dr,poz,v);
        if(arb[2*nod]>arb[2*nod+1])
            arb[nod]=arb[2*nod];
        else
            arb[nod]=arb[2*nod+1];
    }
}

void interogare(int nod,int st,int dr,int inceput,int sfarsit,int &vmax)
{
    if(inceput<=st && dr<=sfarsit)
    {
        if(arb[nod]>vmax)
            vmax=arb[nod];
    }
    else
    {
        int mij=(st+dr)/2;
        if(inceput<=mij)
            interogare(2*nod,st,mij,inceput,sfarsit,vmax);
        if(mij<sfarsit)
            interogare(2*nod+1,mij+1,dr,inceput,sfarsit,vmax);
    }
}
int main()
{
    f>>n>>m;
    for(int i=1;i<=n;i++)
    {
        int x;
        f>>x;
        inserare(1,1,n,i,x);
    }
    for(int i=1;i<=m;i++)
    {
        int r,a,b;
        f>>r>>a>>b;
        if(r==0)
        {
            int vmax=-1;
            interogare(1,1,n,a,b,vmax);
            g<<vmax<<"\n";
        }
        else
        {
            inserare(1,1,n,a,b);
        }
    }
    f.close();
    g.close();
    return 0;
}