Family Tree (for finding Ancestor)

/*facts*/
parent(rakib, soma).
parent(rakib, mimi).
parent(rakib,akash).

parent(soma,rabbi).
parent(soma,ani).

parent(mimi,akib).
parent(mimi,riya).

parent(akash,lima).

parent(rabbi, bikash).
parent(rabbi,urmi).


/*rules*/
ancestor(X,Y):-
parent(X,Y).

ancestor(X,Y):-
parent(X,Z), ancestor(Z,Y).