Cod sursa(job #1954219)

Utilizator ana-maria.simiAna-Maria Simionescu ana-maria.simi Data 5 aprilie 2017 11:48:35
Problema Arbori de intervale Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 1.41 kb
#include <fstream>
using namespace std;
int n,m,x,A,B;
int MaxArb[100001];
int start,finish,val,poz,maxim;

void Update(int,int,int);
void Query(int,int,int);

int main()
{
    freopen("arbint.in" ,"r",stdin);
    freopen("arbint.out" ,"w",stdout);

    scanf("%d%d", &n, &m);
    for(int i=1; i<=n; i++)
    {
        scanf("%d", &x);
        poz=i;
        val=x;
        Update(1,1,n);
    }

    for(int i=1; i<=m; i++)
    {
        scanf("%d%d%d", &x, &A, &B);
        if(x==0)
        {
             maxim=-1;
             start=A;
            finish=B;
             Query(1,1,n);
              printf("%d\n", maxim);
        }
        else
        {
            poz=A;
            val=B;
            Update(1,1,n);
        }
    }
}

void Update(int nod, int left, int right)
{
     if(left==right)
     {
          MaxArb[nod]=val;
          return;
     }

     int div=(left+right)/2;
     if(poz<=div)
        Update(2*nod,left,div);
        else
            Update(2*nod+1,div+1,right);
    MaxArb[nod]=max(MaxArb[2*nod], MaxArb[2*nod+1] );
}

void Query(int nod, int left, int right)
{
     if(start<=left && right<=finish)
     {
          if(maxim<MaxArb[nod])
            maxim=MaxArb[nod];
          return;
     }

     int div=(left+right)/2;
     if(start<=div)
        Query(2*nod,left,div);
     if(div<finish )
        Query(2*nod+1,div+1,right);
}