Beginner: Office BlockedSample answers

As noted in the problem description, there are many ways to represent this. Here we use both the suggested functions mapping persons to storeys and room id numbers and also the converse “occupant” function mapping the rooms back to the persons.

Some definitions make writing the clues a good deal easier. The first one serves to tie together the description in terms of “floor” and “number” with the alternative description in terms of “occupant”. In constraint programming, this kind of thing is called a “channelling constraint”. It is often used in the interests of efficiency, but on this site we use it more for convenience of expression.