Cod sursa(job #2084512)

Utilizator asavu16Andrei Savu asavu16 Data 9 decembrie 2017 10:26:43
Problema Arbori de intervale Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.21 kb
#include <fstream>
#include <algorithm>
using namespace std;
ifstream f("arbint.in");
ofstream g("arbint.out");
int i,n,m,a,b,c,arb[400006],x;

void update (int nod, int a, int b, int poz, int val)
{
    int mij;
    if(a==b)
        arb[nod]=val;
    else
    {
        mij=(a+b)/2;
        if(poz<=mij)update(2*nod,a,mij,poz,val); //updatezi valorile pt intervale
        else update(2*nod+1,mij+1,b,poz,val);
        if(arb[2*nod]>arb[2*nod+1])//te itorci si verifici
        {
            arb[nod]=arb[2*nod];
        }
        else arb[nod]=arb[2*nod+1];
    }
}

int querry (int nod, int a, int b, int qa, int qb)
{
    int mij,rez1,rez2;
    rez1=rez2=-1;
    if(qa<=a&&b<=qb)
    {
        return arb[nod];
    }
    mij=(a+b)/2;
    if(qa<=mij)rez1=querry(2*nod,a,mij,qa,qb);
    if(mij<qb) rez2=querry(2*nod+1,mij+1,b,qa,qb);
    if(rez1>rez2) return rez1;
    else return rez2;
}

int main()
{
    f>>n>>m;
    for(i=1;i<=n;++i)
        {
            f>>x;
            update (1,1,n,i,x);
        }
    for(i=1;i<=m;++i)
    {
        f>>c>>a>>b;
        if(c==1)
        {
            update(1,1,n,a,b);
        }
        else g<<querry(1,1,n,a,b)<<'\n';
    }

}