Adding to a Group / GEO_PointList Alternatives?

[faxingberlin]

I am a beginner who studied HDK. I use VC14(visual studio 15), Houdini 15.5. 

I study many examples in SOP folder and etc... There are two questions.

First,

GA_PointGroup * mygroup;
GEO_Point * ppt;

GR_FOR_ALL_GPOINTS_NC(gdp, GEO_Point, pt)
{
    mygroup->add(ppt->getNum());
}

This Code should be fixed by reference HDK Documents(Geometry Porting Cookbook)

http://www.sidefx.com/docs/hdk/_h_d_k__g_a__porting.html#HDK_GA_PortingCookbook_Simple_Name_Translation

/*
 *Adding To A Group
 *
 *GB Code
 *group->add(prim->getNum())
 *==>
 *GA Code
 *group->add(*prim);
 *group->addIndex(prim->getNum());
*/

GA_PointGroup * mygroup;
GEO_Point * ppt;

GR_FOR_ALL_GPOINTS_NC(gdp, GEO_Point, pt)
{
    mygroup->add(*ppt);
    mygroup->addInex(ppt->getNum());
}

I changed like this. But

mygroup->add(*ppt);

still error...

Is There any way?

 

Second, I have one more question about GEO_PointList

For the Documents,

GB_ElementList

GB had arrays of pointers to objects. As these objects no longer exist, code using element arrays should likely be re-written to be more efficient. The GA version of element lists return by value (not by reference).

// GB Code
GEO_PointList &pnts = gdp->points();
==>
// GA Code
GEO_PointList  pnts = gdp->points();

But there is no GEO_PointList.. I check it existed 13.0 not 15.0
I traverse 13.0 HDK Documents related GEO_PointList.. It's so difficult to find out the replacements.

I search for Major Changes and HDK Forums, Documents. I cannot find. 
I want use points() function.. OTL