How Can I simulate a while loop in Prolog with unchangeable conditions?

Question

So basically I am trying to simulate some C code in Prolog.

It is easy to simulate while loop in Prolog Here is the case:

C code:

int a = 1;
         


        

Answer 1

Not very different from your prolog_while predicate:

prolog_while(N, A) :-
    ( N==0 ->
         true
    ;
         N1 is N -1,
         A1 is A + 1,
         prolog_while(N1, A1)
    ).

But most likely you want the final value of A be available to the caller of this predicate, so you have to return it via an additional argument:

prolog_while(N, A, AFinal) :-
    ( N==0 ->
         AFinal = A
    ;
         N1 is N -1,
         A1 is A + 1,
         prolog_while(N1, A1, AFinal)
    ).