Cod sursa(job #2209750)

Utilizator darkviper17Dark Viper darkviper17 Data 4 iunie 2018 16:44:24
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.11 kb
#include <iostream>
#include <fstream>

using namespace std;

ifstream f("arbint.in");
ofstream g("arbint.out");

const int N=1 << 18, INF=999999999;
int t[N];
int poz,val,a,b;

int intergoare (int p, int st, int dr)
{
    if (a<=st && b>=dr)
        return t[p];

    int m=(st+dr) / 2, r= -INF;

    if (a<=m)
    {
        r=max(r, intergoare( 2*p , st ,m ));
    }

    if (b>m)
    {
        r=max(r, intergoare( 2*p+1 , m+1 , dr ));
    }

    return r;

}

void actualizare(int p, int st, int dr)
{
    if (st==dr)
    {
        t[p]=val;
        return;
    }

    int m=(st+dr)/2;

    if (poz<=m)
    {
        actualizare(2*p,st,m);
    }

    else
    {
        actualizare(2*p+1,m+1,dr);
    }
    t[p]=max( t[ 2*p ], t[ 2*p+1 ] );
}

int main()
{
    int n,m,o,i;
    f>>n>>m;
    for (i=1;i<=n;i++)
    {
        f>>val;
        poz=i;
        actualizare(1,1,n);
    }
    for (i=1;i<=m;i++)
    {
        f>>o;
        if (o==1) {
            f >> poz >> val;
            actualizare(1,1,n);
        }

        if (o==0) {
            f >> a >> b;
            g<<intergoare(1,1,n)<<"\n";
        }
    }
    return 0;
}