poole@CPSC-M-POOLE01 prolog % swipl
Welcome to SWI-Prolog (threaded, 64 bits, version 9.0.4)
SWI-Prolog comes with ABSOLUTELY NO WARRANTY. This is free software.
Please run ?- license. for legal details.

For online help and background, visit https://www.swi-prolog.org
For built-in help, use ?- help(Topic). or ?- apropos(Word).

?- [first].
true.

?- append([1,2,3],[7,8,9],X).
X = [1, 2, 3, 7, 8, 9].

?- append([1,2,3],Z, [1,2,3,4,6,7]).
Z = [4, 6, 7].

?- append(A,B,[1,2,4,6,8]).
A = [],
B = [1, 2, 4, 6, 8] ;
A = [1],
B = [2, 4, 6, 8] ;
A = [1, 2],
B = [4, 6, 8] ;
A = [1, 2, 4],
B = [6, 8] ;
A = [1, 2, 4, 6],
B = [8] ;
A = [1, 2, 4, 6, 8],
B = [] ;
false.

?- append([1,2],X,[5,6,7]).
false.

?- append(X,[3|Y],[1,2,3,4,5,4,3,2]).
X = [1, 2],
Y = [4, 5, 4, 3, 2] ;
X = [1, 2, 3, 4, 5, 4],
Y = [2] ;
false.

?- del1(a,[a,v,a,t,a,r],A).
A = [v, a, t, a, r] ;
A = [a, v, t, a, r] ;
A = [a, v, a, t, r] ;
false.

?- del1(b,[a,v,a,t,a,r],A).
false.

?- del1(b,X,[a,av,at]).
X = [b, a, av, at] ;
X = [a, b, av, at] ;
X = [a, av, b, at] ;
X = [a, av, at, b] ;
false.

?- [family].
true.

?- parent(X,xavier).
X = sophie ;
X = justin.

?- grandmother(X,xavier).
X = margaret ;
X = estelle ;
false.

?- sibling(A,B).
A = justin,
B = alexandre ;
A = justin,
B = michel ;
A = alexandre,
B = justin ;
A = alexandre,
B = michel ;
A = michel,
B = justin ;
A = michel,
B = alexandre ;
A = xavier,
B = ella_grace ;
A = ella_grace,
B = xavier ;
A = justin,
B = alexandre ;
A = justin,
B = michel ;
A = alexandre,
B = justin ;
A = alexandre,
B = michel ;
A = michel,
B = justin ;
A = michel,
B = alexandre ;
A = xavier,
B = ella_grace ;
A = ella_grace,
B = xavier ;
false.

?- append(A,B,C).
A = [],
B = C ;
A = [_A],
C = [_A|B] ;
A = [_A, _B],
C = [_A, _B|B] ;
A = [_A, _B, _C],
C = [_A, _B, _C|B] .

?- append(X,Y,Z).
X = [],
Y = Z ;
X = [_A],
Z = [_A|Y] ;
X = [_A, _B],
Z = [_A, _B|Y] .

?- [elect_prop].
true.

?- lit_l2.
true.

?- lit_l1.
false.

?- [elect_prop].
true.

?- lit_l1.
true .

?-