Cod sursa(job #962354)

Utilizator ard_procesoareLupicu ard_procesoare Data 14 iunie 2013 17:18:18
Problema Arbori de intervale Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.27 kb
#include <fstream>
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
#define NMAX 400010
#define INF -999999999
int arb[NMAX],n,m,left,right;
int start,ed,pos,val;
void update(int nod,int left,int right);
int query(int nod,int left,int right);
inline int maxim(int a,int b)
{
    if(a>b) return a;
    return b;
}
int main()
{
    fin>>n>>m;
    for(pos=1;pos<=n;pos++)
    {
        fin>>val;
        update(1,1,n);
    }
    int a,b,x;
    for(int i=1;i<=m;i++)
    {
        fin>>x>>a>>b;
        if(!x)
        {
            start=a;
            ed=b;
            fout<<query(1,1,n)<<"\n";
        }
        else
        {
            pos=a;val=b;
            update(1,1,n);
        }
    }

}
void update(int nod,int left,int right)
{
    if(left==right)
    {
        arb[nod]=val;
        return;
    }
    int m=(left+right)/2;
    if(pos<=m) update(2*nod,left,m);
    else update(2*nod+1,m+1,right);
    arb[nod]= maxim(arb[2*nod],arb[2*nod+1]);
}
int query(int nod,int left,int right)
{
    if(start<= left && right<= ed)
        return arb[nod];
    int m=(left+right)/2,m1=INF,m2=INF;
    if(start<=m) m1=query(2*nod,left,m);
    if(m+1<=ed) m2=query(2*nod+1,m+1,right);
    return maxim(m1,m2);
}