Copying slides between presentations and applying destination presentations master part

We are copying slides from one presentation to another using logic given at http://msdn.microsoft.com/en-us/library/office/ee361883(v=office.12).aspx. This adds a new slide master part for every slide from the source. Instead we want to be able to add slides and inherit the slide master of the destination presentation just as it happens when we copy and paste the slide manually. We should also be add the slide layout part of source slide if does not already exist in the destination slide master. Any pointers would be really helpful.