prolog - 在序言中嵌套 for 循环

Question

我对 Prolog 很陌生，所以我不确定如何做到这一点。

我正在尝试创建一个嵌套的 for 循环，在每一行输出三个变量。

我正在尝试获得如下循环的输出:

SWI-序言

?- out(A, B, C).

A = 1, B = 1, C = 1 (Next)
A = 1, B = 1, C = 2 (Next)
A = 1, B = 2, C = 1 (Next)

A = 1, B = 2, C = 2 (Next)
A = 2, B = 1, C = 1 (Next)
A = 2, B = 1, C = 2 (Next)

A = 2, B = 2, C = 1 (Next)
A = 2, B = 2, C = 2 (Next)

它需要有一个自定义范围

在 Python 中它看起来像这样

for i in range(1,3):
    for j in range(1,3):
        for k in range(1,3):
        print(i, j, k)

Answer 1

out(A, B, C) :-
    maplist(between(1, 2), [A, B, C]).

结果:

?- out(A, B, C).
A = B, B = C, C = 1 ;
A = B, B = 1,
C = 2 ;
A = C, C = 1,
B = 2 ;
A = 1,
B = C, C = 2 ;
A = 2,
B = C, C = 1 ;
A = C, C = 2,
B = 1 ;
A = B, B = 2,
C = 1 ;
A = B, B = C, C = 2.