prolog - 在序言中，如何编写Quicksort是使用第二元素作为枢纽？(In prolog, how to write Quicksort is use second element as pivot?)

Question

In my example, I have done to use the first (left-most) element of the given list is selected as the pivot.

(在我的示例中，我已完成将给定列表的第一个（最左侧）元素用作枢轴的选择。)

qsort([],[]):- !.
qsort([Pivot|Tail],Sorted):-
        split(Pivot,Tail,Less,Greater),
        qsort(Less,SortedLess),
        qsort(Greater,SortedGreater),
        append(SortedLess,[Pivot|SortedGreater],Sorted).
split(_,[],[],[]).
split(Pivot,[X|T],[X|Less],Greater):-
        X=<Pivot,split(Pivot,T,Less,Greater).
split(Pivot,[X|T],Less,[X|Greater]):-
        X>Pivot,split(Pivot,T,Less,Greater).

However, I am wondering how to use the second element as pivot

(但是，我想知道如何使用第二个元素作为枢轴)

  ask by SkaraBrae translate from so

Answer 1

等待大神答复