compare element in a list prolog

hi all,
im new to prolog

and im trying to make this pred.

compare[a,a,a,a].
yes


compare[a,e,a,t].
no


so if the element of the list are the same then its a yes  if not then its a
 no

how can i do this?

i was trying this but it didnt work

compare([H|T]):-
element(H, [H|T]).
element(H, [H|T]):-
element(H,T).

but this is wronge.  anyone can help me plz?

urdad@hotmail.com (kimos) writes:

> hi all,
> im new to prolog
>
> and im trying to make this pred.
>
> compare[a,a,a,a].
> yes
>
>
> compare[a,e,a,t].
> no
>
>
> so if the element of the list are the same then its a yes  if not then its
 a no
>
> how can i do this?
>
> i was trying this but it didnt work
>
> compare([H|T]):-
> element(H, [H|T]).
> element(H, [H|T]):-
> element(H,T).
>
> but this is wronge.  anyone can help me plz?

What is element's base case?  It needs a fact to know if the recursive
procedure is successful by stating how the final step should appear.

Hopefully this hint will provoke you to add a simple line of code.
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