Solution to part (b).

• Maybe we want some measure of quality rather than just a time limit (e.g., we may want the shortest presentation).
• We may want to return the best presentation first.
• We may want a sensible order to the presentation. (The current versions don't worry about the order of the clips within a presentation).
• We may want some continuity for the presentations; the video should flow, and be coherent.
• What presentation a person wants may not only depend on what they are interested in, but what they already know about.
• The terms used to describe the topics for the user may not necessarily match with the topics in the segments database. For example, they may just want something about CS research, in which case either computational intelligence or graphics would be OK. The system should do this automatically (the user needn't know that there is computational intelligence research going on).
• There should still be a presentation if some topic cannot be covered. In this case we want the best presentation.
• The user may not know what sorts of things are in the video, even though they may be interested in it. We would like to implement "give me an interesting video that matches what I am interested in".