Cod sursa(job #2935344)

Utilizator alessiamtr12Mitrica Alessia alessiamtr12 Data 6 noiembrie 2022 16:11:52
Problema Arbori de intervale Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.16 kb
#include <fstream>

using namespace std;
ifstream fin("arbint.in");
ofstream fout("arbint.out");
int n,x,a,b,aint[400001],q,op,poz,val,maxx;
void update(int nod, int st, int dr)
{
    if(st==dr)
        aint[nod]=val;
    else
    {
        int mid=(st+dr)/2;
        if(poz<=mid)
            update(2*nod,st,mid);
        else
            update(2*nod+1,mid+1,dr);

        aint[nod]=max(aint[2*nod],aint[2*nod+1]);
    }
}
void query(int nod,int st,int dr,int a,int b)
{
    if(a<=st && dr<=b)
    {
        maxx=max(maxx,aint[nod]);
    }
    else
    {
        int mid=(st+dr)/2;
        if(a<=mid)
            query(2*nod,st,mid,a,b);
        if(b>=mid+1)
            query(2*nod+1,mid+1,dr,a,b);
    }
}
int main()
{
    fin>>n>>q;
    for(int i=1; i<=n; i++)
    {
        fin>>val;
        poz=i;
        update(1,1,n);
    }
    for(int i=1; i<=q; i++)
    {
        fin>>op>>a>>b;
        if(op==0)
        {
            maxx=0;
            query(1,1,n,a,b);
            fout<<maxx<<"\n";
        }
        else
        {
            poz=a;
            val=b;
            update(1,1,n);
        }
    }
    return 0;
}