Cod sursa(job #200913)

Utilizator AndreiDDiaconeasa Andrei AndreiD Data 27 iulie 2008 13:32:39
Problema Arbori de intervale Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.13 kb
#include <stdio.h>
#define NMAX 400000
int arbore[NMAX];
int v[NMAX],maxim,n,m,a,b,mij,i,x;
  
  

int max(int a, int b)
{
if (a>b) return a;
else return b;
}

void interogare(int st,int dr,int nod)
{
if (a<=st && dr<=b)
   if (maxim<arbore[nod])
      maxim=arbore[nod];
   else
      {
      mij=(st+dr)/2;
      if (a<=mij)
	 interogare(st,mij,2*nod);
      if (b>mij)
	 interogare(mij+1,dr,2*nod+1);
      }
}   
  
  
void actualizare(int nr,int st,int dr,int nod)
{
if (st==dr)
   arbore[nod]=b;
   else
      {
      mij=(st+dr)/2;
      if (nr<=mij)
      actualizare(nr,st,mij,2*nod);
      else
      actualizare(nr,mij+1,dr,2*nod+1);
      arbore[nod]=max(arbore[2*nod],arbore[2*nod+1]);
}
}
  
  
  
int main()
{
freopen("arbint.in","rt",stdin);
freopen("arbint.out","wt",stdout);
scanf("%d %d",&n, &m);
for (i=1;i<=n;i++)
    {
    scanf("%d",&b);
    actualizare(i,1,n,1);
    }
for (i=1;i<=m;i++)
    {
    scanf("%d %d %d",&x,&a,&b);
    if (x)
       actualizare(a,1,n,1);
       else
	  {
	  maxim=0;
	  interogare(1,n,1);
	  printf("%d\n",maxim);
	 }
	}
return 0;
}