Cod sursa(job #200907)

Utilizator AndreiDDiaconeasa Andrei AndreiD Data 27 iulie 2008 13:14:07
Problema Arbori de intervale Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.12 kb
#include <stdio.h>
#define NMAX 1010


int n,m,cif,a,b,i;
int arbore[NMAX];
int maxim,x,mij;

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

void actualizare(int nod,int st,int dr,int nr)
{
if (st==dr)
    arbore[nod]=x;
    else
      {
      mij=(st+dr)/2;
      if (nr<=mij)
	  actualizare(2*nod,st,mij,nr);
	  else
	  actualizare(2*nod+1,mij+1,dr,nr);
	 }
arbore[nod]=max(arbore[2*nod],arbore[2*nod+1]);
}



void interogare(int nod,int st,int dr)
{
if (st>=a && dr>=b)
   if (maxim<arbore[nod])
       maxim=arbore[nod];
else
   {
   mij=(st+dr)/2;
   if (a<=mij)
      interogare(2*nod,st,mij);
      else
      if (b>mij)
	 interogare(2*nod+1,mij+1,dr);
   }
}




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", &x);
    actualizare(1,1,n,i);
     }
for (i=1;i<=m;++i)
    {   
     scanf("%d %d %d",&cif, &a, &b);
     if (cif)
	actualizare(1,1,n,a);
	else
	{
	 maxim=0;
	 interogare(1,1,n);
	 printf("%d\n", maxim);
        }   
    }
return 0;
}