Non-mandatory prolog exercise

Part 1 : 

Exercises combining some of the curriculum about types and subtypes from Eyvind's lectures with 
some SML stuff and of course Prolog.

Some of these exercises are probably a little hard and goes a bit outside the normal exam exercises for Prolog in this course.

Check out old exams to see the normal difficulty of prolog exercises on the exams.

Link : Prolog exercise

Part 2 : 

Question 3 (a,b,c) in Exam 2015

There is an error in 3c Exam2015. The 3 and 5 value in the heap should be switched, so that the heap is actually a heap.

There will be a detailed solution available after a week or so.