words.pl

/*  File: words.pl  (Sol): Mihaela Malita IMPROVE!
    Title: For finding word squares 3x3
Generates word squares.
A word square is an arrangement of letters in a square such that each row and each column is a word in the dictionary.
?- start.
Solution for wordsquare
	t-a-b
	e-p-a
	n-e-t
Algorithm:
0) Fix your vocabulary (lexicon).
1) Write down your square with variables:
	A-B-C
	D-E-F
	G-H-I
2) Put condition: all row and columns are words:
   For rows:
	word([A,B,C]).  word([D,E.F]).  word([G,H,I]).
   For colums:
	word([A,D,G]).  word([B,E.H]).  word([C,F,I]).
3) Put together all the variables you look for in one predicate.
	wordsq(A,B,C,D,E,F,G,H,I).
4) Write start. Look for all solutions.
*****************************************************/

:- encoding(utf8).

/* data base with words */
word([t,a,b]).  word([e,p,a]).
word([b,a,t]).  word([t,e,n]).
word([t,a,n]).  word([r,a,t]).
word([r,a,n]).  word([a,t,e]).
word([j,a,b]).  word([j,o,e]).
word([b,e,t]).  word([a,p,e]).
word([n,e,t]).  word([a,p,t]).
word([o,f,t]).  word([o,p,t]).

wordsq(A,B,C,D,E,F,G,H,I) :-
	word([A,B,C]),word([D,E,F]),
	word([G,H,I]),word([A,D,G]),
	word([B,E,H]),word([C,F,I]).
/* Just one solution
start :- write('Solution for wordsquare\n'),
	wordsq(A,B,C,D,E,F,G,H,I),
	write(A-B-C), nl,
	write(D-E-F), nl,
	write(G-H-I).
---------------------------------------------*/
/* All solutions   */
start :-
	write('Solution for wordsquare\n'),
	forall(wordsq(A,B,C,D,E,F,G,H,I),
		   (write('\nWord Square:\n'),
			write(A-B-C), nl,
			write(D-E-F), nl,
			write(G-H-I))).