prolog

问题 I am trying to write a predicate permutation/2 so that it is true if and only if both arguments are list, one a permutation of the other. To do this, I've written the two helper predicates delete/3 and insert/3 . The first is true if and only if the third argument is the second argument, both lists, with the first instance of the element in the first argument removed. The second is true if and only if the third argument equals the second argument with the first argument (element) inserted.

问题 Considering the following Prolog program : reverse_bits([1], [0]). reverse_bits([0], [1]). reverse_bits([H|T], [0|R]) :- H==1, reverse_bits(T, R). reverse_bits([H|T], [1|R]) :- H==0, reverse_bits(T, R). What's the SLD tree for the question above ? reverse_bits(Input, [1, 0, 0]).? It's not valid so does it even exist a SLD tree ? 回答1: Here is a minimal example using the sldnfdraw package. First, generate a program and query using the syntax specified in the library documentation: % estamos.pl

问题 Markus Triska has reported an algorithm to determine strongly connected components (SCC). Is there a solution which determines the SCC without making use of attributed variable and that can work anytime. So that some vertices can have infinitely many edges? I am asking because I am wondering whether B-Prologs anytime tabling which they call eager can be replicated. B-Prolog determines clusters which is their name for SCC. But it has also a tabling mode where it returns tabled results eagerly.

问题 I am trying to run the following program in Prolog. mama_mia1(A,M,LI,HI,LO,HO,AA) :- p1(A,M,LI,HI,LO,HO,PROGS), reverse(PROGS,PROG), atom_chars(AA,PROG), !. p1(_,_,LO,LO,LO,_,[]). p1(_,_,HO,HO,_,HO,[]). p1(_,_,LO,HO,LO,HO,[]). p1(_,_,X,LO,LO,HO,[]) :- X>LO,X<HO. p1(_,_,X,HO,LO,HO,[]) :- X>LO,X<HO. p1(_,_,LO,Y,LO,HO,[]) :- Y>LO,Y<HO. p1(_,_,HO,Y,LO,HO,[]) :- Y>LO,Y<HO. p1(_,_,X,Y,LO,HO,[]) :- X>LO,X<HO,Y>LO,Y<HO. p1(A,M,X,Y,LO,HO,PROG) :- ( (X1 is X+A, H1 is HO+1, X1<H1, Y1 is Y+A, Y1<H1 ) ->

问题 I am trying to run the following program in Prolog. mama_mia1(A,M,LI,HI,LO,HO,AA) :- p1(A,M,LI,HI,LO,HO,PROGS), reverse(PROGS,PROG), atom_chars(AA,PROG), !. p1(_,_,LO,LO,LO,_,[]). p1(_,_,HO,HO,_,HO,[]). p1(_,_,LO,HO,LO,HO,[]). p1(_,_,X,LO,LO,HO,[]) :- X>LO,X<HO. p1(_,_,X,HO,LO,HO,[]) :- X>LO,X<HO. p1(_,_,LO,Y,LO,HO,[]) :- Y>LO,Y<HO. p1(_,_,HO,Y,LO,HO,[]) :- Y>LO,Y<HO. p1(_,_,X,Y,LO,HO,[]) :- X>LO,X<HO,Y>LO,Y<HO. p1(A,M,X,Y,LO,HO,PROG) :- ( (X1 is X+A, H1 is HO+1, X1<H1, Y1 is Y+A, Y1<H1 ) ->

问题 In SWI-Prolog, I am using code such as at the beginning of a module text file: :- module(foo, [bar/2]). :- use_module(library(jack)). I don't want to change my code . How can I neverthelss use ECLiPSe Prolog (*). Is there some library that defines a module/2 directive in ECLiPSe Prolog? Best Regards (*) http://eclipseclp.org/ 回答1: The following code defines a macro that maps module/2 into module/3 directives: :- export macro((:-)/1, translate_directive/2, [top_only]). translate_directive( (:-

问题 I am studying for a logic test and I saw an example of Perfect number problem There is many solutions to this however there is one that I am unsure how they have done it. divisors(Number, D, L1, L2) :- X is Number / D, ( D < X -> D1 is D + 1, divsors(Number, D1, L1, L2) ; L1 = L2). divisors(Number, D, L1, L2) :- 0 is Number mod D, D1 is D + 1, X is Number / D, ( D =< X -> divisors(Number, D1, [X, D |L1], L2) ; L1 = L2). 来源： https://stackoverflow.com/questions/47744880/cant-understand-prolog

问题 The homework is to take in two variables, a number between 0 and 10,000 and a number of how many circular primes there are between 1 and that number. I am having trouble passing the variable back up through the recursion (backtracing is what it is called, I think.) I get the right number and I am pretty sure I have the concept down, the problem I am having is that it throws an error when I try to reassign a variable (?!) Here is the code: circPrimeCompare(Below, NumCirc):- RealNum is 0,

问题 Let's say i have some data in this form: plot('Jurrassic Park",'action') plot('Jurrassic Park",'drama') plot('Jurrassic Park",'adventure') plot('pulp fiction",'retro') plot('pulp fiction",'crime') .... where in plot(X,Y) X is a movie and Y is this movies genre. What i would like to do is query this database and get all the movies that have 3 equal genres. For example if there is another movie that is action,drama,adventure i would like it to be paired with Jurassic park.What i have done so

问题 Let's say i have some data in this form: plot('Jurrassic Park",'action') plot('Jurrassic Park",'drama') plot('Jurrassic Park",'adventure') plot('pulp fiction",'retro') plot('pulp fiction",'crime') .... where in plot(X,Y) X is a movie and Y is this movies genre. What i would like to do is query this database and get all the movies that have 3 equal genres. For example if there is another movie that is action,drama,adventure i would like it to be paired with Jurassic park.What i have done so