To represent the standard version of the map colouring problem, we need to add a constraint that two adjacent countries cannot be coloured the same colour. In ASP, this constraint can be written as a clause of the form: :- country(C1), country(C2), adjacent(C1, C2), colour(C1, X), colour(C2, X).
To represent the standard version of the map colouring problem, we need to add a constraint that two adjacent countries cannot be coloured the same colour. In ASP, this constraint can be written as a clause of the form: :- country(C1), country(C2), adjacent(C1, C2) colour(C1, X), colour(C2, X).