#lang datalog

% It finds whether a parent is a father or a mother depending on the gender of the parent.



% Opgave 2

% In the first program, a person is only happy if he/she is both rich and famous.
% In the second program, a person is happy if he/she is either rich or famous.


% Opgave 3

% There is one program containing 3 clauses.
% The first two clauses are called facts each only containing a single atom.
% The first two facts each contain a atom with the single term beyonce which is a constant

% Last line is a clause with a head and a body containing two atoms.
% The body uses the predicates created in the last two lines, while the clause introduces the new predicate happy.
% The clause uses the variable Person, which is used once in all 3 atoms.


% Opgave 4

destinct(red, green).
destinct(green, blue).
destinct(red, blue).

% It is symmetric
destinct(X, Y) :- destinct(Y, X).

colouring(X, Y, XC, YC) :- neighbour(X, Y), destinct(XC, YC).