Re: Help with PROLOG predicates

From: Martin Sondergaard (nobody_at_nowhere.com)
Date: 12/03/03

  • Next message: Jan Wielemaker: "Re: reading the output of a program?" 
    Date: Wed, 3 Dec 2003 18:24:06 -0000

    > 2) even_length/1. Succeeds (true) if the list given by
    the
    > parameter has even number of elements. Do not use arithmetic.
    >
    > Examples:
    >
    > 34 ?- even_length([a, b, c]).
    >
    > No
    >
    > 35 ?- even_length([a, b, c, c]).
    >
    > Yes
    >
    > 36 ?- even_length([]).
    >
    > Yes
    >

    Here is a hint for that problem.
    The solution is something like this ...

    even_length( ... ) :- ...
    even_length([_, _]).
    even_length( ... ) :- 

    --
Martin Sondergaard.
  • Next message: Jan Wielemaker: "Re: reading the output of a program?"