Prolog：有没有办法在列表中找到最长的连续数序列并获得其长度？

Question

给定5个随机数字的列表（数字范围从1到13），即[1,6,11,12,13]，我如何找到连续最长的数字序列（即[11,12,13 ]）它的长度必须更大或等于3，并且还必须获得长度？

Answer 1

您可以遍历列表，跟踪当前序列及其长度以及迄今为止找到的最大序列和长度。

处理完所有列表后，您可以检查最大长度是否 >= 3 并选择正确的输出：

longest_sequence([First|L], Len1, Seq) :-
    longest_sequence(L, 1, [First], 0, [], Len, RSeq),
    (   Len>=3
    ->  reverse(RSeq, Seq),
        Len1=Len
    ;   Seq=[],
        Len1=0
    ).
  
longest_sequence([], CurLen, CurSeq, MaxLen, MaxSeq, Len, Seq):-
  (CurLen > MaxLen -> Len-Seq=CurLen-CurSeq ; Len-Seq=MaxLen-MaxSeq).
longest_sequence([CurItem|L], CurLen, [LastItem|CurSeq], MaxLen, MaxSeq, Len, Seq):-
  (
   succ(LastItem, CurItem) ->
    (
      succ(CurLen, CurLen1),
      CurSeq1=[CurItem,LastItem|CurSeq],
      MaxLen1-MaxSeq1=MaxLen-MaxSeq
    ) ;
    (
      (CurLen > MaxLen -> MaxLen1-MaxSeq1=CurLen-[LastItem|CurSeq] ; MaxLen1-MaxSeq1=MaxLen-MaxSeq),
      CurLen1=1,
      CurSeq1=[CurItem]
    )
   ),
   longest_sequence(L, CurLen1, CurSeq1, MaxLen1, MaxSeq1, Len, Seq).

示例运行：

?- longest_sequence([1,6,11,12,13], Len, Seq).
Len = 3,
Seq = [11, 12, 13].

?- longest_sequence([1,6,11,12,13,2,3,4,5], Len, Seq).
Len = 4,
Seq = [2, 3, 4, 5].

?- longest_sequence([1,2], Len, Seq).
Len = 0,
Seq = [].

Answer 2

def longestSeq(n):
    seqMax = 0
    counter = 0
    i = 0
    while i+1 < len(n):
        curr = n[i+1]
        last = n[i]

        
        sub = curr - last

        if sub == 1:
            if counter == 0:
                counter = 2 
            else:
                counter += 1 
        else:
            if counter > 0:
               if seqMax < counter:
                   seqMax = counter
                   counter = 0 
        i += 1 

    if seqMax < counter:
        seqMax = counter

    if seqMax >= 3:
        return seqMax
    else:
        return 0