Cod sursa(job #1851615)

Utilizator razvan99hHorhat Razvan razvan99h Data 19 ianuarie 2017 22:00:53
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.05 kb
#include <iostream>
#include <fstream>
#define DM 100005
using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int arb[DM*4], n, m, i, var, a, b;

void update(int nod, int st, int dr, int poz, int val)
{
    if(st==dr)
    {
        arb[nod]=val;
        return;
    }
    int mij=(st+dr)/2;
    if(poz<=mij)
        update(nod*2,st,mij,poz,val);
    else
        update(nod*2+1,mij+1,dr,poz,val);
    arb[nod]=max(arb[nod*2],arb[nod*2+1]);
}
int query(int nod, int st, int dr, int a, int b)
{
    if(a<=st && dr<=b)
        return arb[nod];
    int mij=(st+dr)/2, ret=-(1<<31)+1;
    if(a<=mij)
        ret=max(ret,query(nod*2,st,mij,a,b));
    if(mij+1<=b)
        ret=max(ret,query(nod*2+1,mij+1,dr,a,b));
    return ret;
}

int main()
{
    fin>>n>>m;
    for(i=1;i<=n;i++)
    {
        fin>>var;
        update(1,1,n,i,var);
    }
    for(i=1;i<=m;i++)
    {
        fin>>var>>a>>b;
        if(var==0)
            fout<<query(1,1,n,a,b)<<'\n';
        else update(1,1,n,a,b);
    }
    return 0;
}