karate.logic

国外的一套开源CRM

/*
To run this program use the query: 
    geneval(Solution)
which should produce the result:
    Solution = [student(amy, hightower, shootFighting), student(betti, ellis, sparring), student(carla, fowler, childrens), student(dianne, goodrich, pressurePoints)]
    no more results
*/

/*
 * This program solves the following puzzle:
 * 
 * Each of four martial arts students has a different specialty. 
 * From the following clues, can you determine each student's 
 * full name and her special skill? 
 *
 *   1. Ms. Ellis (whose instructor is Mr. Caldwell), Amy, and 
 *      Ms. Fowler are all martial arts students. 
 *   2. Sparring isn't the specialty of either Carla or Dianne. 
 *   3. Neither the shoot fighting expert nor the pressure 
 *      point fighter is named Fowler. 
 *   4. Childrens techniques aren't the specialty of Dianne 
 *      (whose instructor is Ms. Sherman). 
 *   5. Amy, who disdains pressure point fighting, isn't Ms. 
 *      Goodrich. 
 *   6. Betti and Ms. Fowler are roommates.
 *   7. Ms. Hightower avoids sparring because of its point 
 *      scoring nature.
 */
geneval(Solution) :-
    generate(Solution),
    evaluate(Solution);

// generate all possible solutions
select(X, [X | Rest], Rest);
select(X, [Y | Rest1], [Y | Rest2]) :- 
    select(X, Rest1, Rest2);

permutation(InList, [H | OutRest]) :- 
    select(H, InList, InOther), 
    permutation(InOther, OutRest);
permutation([], []);

generate(Solution) :-
    permutation(
        ["ellis", "fowler", "goodrich", "hightower"], 
        LastNames),

    permutation(
        ["sparring", "shootFighting", "pressurePoints", "childrens"], 
        Specialties),

    associate(
        ["amy", "betti", "carla", "dianne"], 
        LastNames, 
        Specialties, 
        Solution);

// "associate" combines three lists into one list of 
// students with three attributes

associate(
    [FirstName | Frest], 
    [LastName | Lrest], 
    [Specialty | Srest], 
    [student(FirstName, LastName, Specialty) | 
     StudentsRest]) 

    :- associate(
        Frest, 
        Lrest, 
        Srest, 
        StudentsRest);

associate([], [], [], []);

// "evaluate" takes a list of "student" structures, and 
// succeeds if all the criteria are met.

member(X, [X | Rest]);
member(X, [Y | Rest]) :- member(X, Rest);

evaluate(Solution) :-
    // Clue 1
    not member(student("amy", "ellis", _), Solution),
    not member(student("amy", "fowler", _), Solution),

    // Clue 2
    not member(student("carla", _, "sparring"), Solution),
    not member(student("dianne", _, "sparring"), Solution),

    // Clue 3
    not member(student(_, "fowler", "shootFighting"), Solution),
    not member(student(_, "fowler", "pressurePoints"), Solution),

    // Clue 4
    not member(student("dianne", _, "childrens"), Solution),

    // Clue 5
    not member(student("amy", "goodrich", _), Solution),
    not member(student("amy", _, "pressurePoints"), Solution),

    // Clue 6
    not member(student("betti", "fowler", _), Solution),

    // Clue 7
    not member(student(_, "hightower", "sparring"), Solution),

    // Clue 4, 1
    not member(student("dianne", "ellis", _), Solution);