:- use_module(contestlib,[for/3]).

kay4(N) :-
	for(X,1,N),
	for(Y,1,N),
	point_contains(X,Y,N,C),
	write(C),
	fail.

point_contains(1,1,_,C) :- !, C = a.
point_contains(1,N,N,C) :- !, C = 'b\n'.
point_contains(1,_,_,C) :- !, C = '-'.
point_contains(N,1,N,C) :- !, C = c.
point_contains(N,N,N,C) :- !, C = 'd\n'.
point_contains(N,_,N,C) :- !, C = '-'.
point_contains(_,1,_,C) :- !, C = '|'.
point_contains(_,N,N,C) :- !, C = '|\n'.
point_contains(X,Y,N,C) :-
	(X =< N//2 ; (N - X) < N//2), !,
	( X == Y ->
	    C = '\\'
	; X + Y =:= N + 1 ->
	    C = '/'
	;
	    C = ' '
	).
point_contains(_,Y,N,C) :- 
	( Y =:= N//2 + 1 ->
	    C = 'X'
	;
	    C = ' '
	).