Cod sursa(job #1673927)

Utilizator sorynsooSorin Soo sorynsoo Data 4 aprilie 2016 11:18:18
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.16 kb
#include <fstream>
using namespace std;
ifstream cin("arbint.in");
ofstream cout("arbint.out");
#define MAXN 100005

int arb[MAXN*4];
int n, m, x, poz, a, b, maxim;

void update(int nod, int st, int dr)
{
    if(st == dr)
    {
        arb[nod] = x;
        return;
    }

    int mij = ( st + dr )/2;
    if(poz <= mij)
        update(nod*2, st, mij);
    else
        update(nod*2+1, mij+1, dr);

    arb[nod] = max(arb[nod*2], arb[nod*2+1]);
}

void query(int nod, int st, int dr)
{
    if(a<=st && b>=dr)
    {
        maxim = max(maxim, arb[nod]);
        return;
    }

    int mij = ( st + dr )/2;
    if(a<=mij)
        query(nod*2, st, mij);
    if(b>mij)
        query(nod*2+1,mij+1, dr);
}

int main()
{
    int i, tip;
    cin>>n>>m;
    for(i=1; i<=n; i++)
    {
        cin>>x;
        poz=i;
        update(1,1,n);
    }

    for(i=1; i<=m; i++)
    {
        cin>>tip;
        if(!tip)
        {
            maxim = -1;
            cin>>a>>b;
            query(1,1,n);
            cout<<maxim<<"\n";
        }
        if(tip)
        {
            cin>>poz>>x;
            update(1,1,n);
        }
    }
}