Cod sursa(job #981059)

Utilizator rzvrzvNicolescu Razvan rzvrzv Data 6 august 2013 12:34:53
Problema Arbori de intervale Scor 50
Compilator cpp Status done
Runda Arhiva educationala Marime 1.25 kb
#include<cstdio>

using namespace std;

int x,y,t[400000],a[100006],b[100006],n,i,m,tip;

int Max(int a,int b)
{
    if (a>b)
        return a;
    else return b;
}

void update (int Nod,int st,int dr,int poz,int val)
{
    if (st==poz&&dr==poz)
    {
        t[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);
    if (t[Nod*2]>t[Nod*2+1])
        t[Nod]=t[Nod*2];
    else t[Nod]=t[Nod*2+1];
}

int query(int Nod,int st,int dr,int x,int y)
{
    if (x<=st&&dr<=y)
    {
        return t[Nod];
    }
    int mij=(st+dr)/2;
    int sol=-2000000001;
    if (x<=mij)
    {
        sol=Max(sol,query(Nod*2,st,mij,x,y));
    }
    if (mij<y)
        sol=Max(sol,query(Nod*2+1,mij+1,dr,x,y));
    return sol;
}

int main()
{
    freopen("arbint.in","r",stdin);
    freopen("arbint.out","w",stdout);
    scanf("%d%d",&n,&m);
    for (i=1;i<=n;i++)
    {
        scanf("%d",&a[i]);
        update(1,1,n,i,a[i]);
    }
    for (i=1;i<=m;i++)
    {
        scanf("%d%d%d",&tip,&x,&y);
        if (tip==1)
        {
            update(1,1,n,x,y);
        }
        else printf("%d\n",query(1,1,n,x,y));
    }
}