my_length(List, Length) :-
my_length(List, 0, Length).
my_length([], Length, Length).
my_length([_| Tail], Acc, Length) :-
Acc2 is Acc + 1,
my_length(Tail, Acc2, Length).
:- dynamic(pred_plain/1).
plain_dyndb(N) :-
assertz(pred_plain(N)),
retract(pred_plain(N)).
my_between(Lower, _, Lower).
my_between(Lower, Upper, Integer) :-
Lower < Upper,
Next is Lower + 1,
my_between(Next, Upper, Integer).
my_repeat(_).
my_repeat(N) :-
N > 1,
N2 is N - 1,
my_repeat(N2).
% generate a list containing the first N non-negative integers
generate_list(N, List) :-
generate_list(0, N, List).
generate_list(N, N, []) :-
!.
generate_list(M, N, [M| Ms]) :-
M < N,
M2 is M + 1,
generate_list(M2, N, Ms).
