Question

对于由整数和数字列表组成的异构列表，请编写谓词以计算表示为子列表的所有数字的总和。例如：[1，[2、3]，4、5，[6、7、9]，10、11，[1、2、0]，6] => [8、2、2]。

% The predicate reverses the given list.
% reverseList(L - list of integers, X - output, Z - auxiliary list )
% reverseList(i,o,i)
reverseList([],Z,Z).
reverseList([H|T],X,Rest):- reverseList(T,X,[H|Rest]).

% The predicate returns the reverse list of the given list.
% wrapperReverseList(L - list of integers, R - output list).
% wrapperReverseList(i,o)
wrapperReverseList(L,R):- reverseList(L,R,[]).

% The predicate adds two numbers represented as lists.
% sum(L1 - first number as list, L2 - second number as list,
%              T - transport integer, R - result list)
% sum(i,i,i,o).
sum([],[],T,[T]):-T=\=0,!.
sum([],[],_,[]):-!.
sum([],[L],T,[L]):-T=0,!.
sum([L],[],T,[L]):-T=0,!.
sum([H1|T1],[H2|T2],T,[Hs|Ts]):-
      S is H1+H2+T,
      Tn is S div 10,
      Hs is S mod 10,
      sum(T1,T2,Tn,Ts).

% The predicate adds two number represented as lists.
% wrapperSum(L1 - first number as list, L2 - second number as list, R -
%                                                          result list )
% wrapperSum(i,i,o)
wrapperSum(L1,L2,Ls):-
    wrapperReverseList(L1,L1i),
    wrapperReverseList(L2,L2i),
    sum(L1i,L2i,0,LAux),
    wrapperReverseList(LAux,Ls).

% until here the code checks out, adding two lists works   

% now i want to go through a list, check for each element if it is a list,
% and if it is, add it to the result

addLists([],[],_).
addLists([H|T],Laux,R):-is_list(H),
    wrapperSum(H,Laux,R1),
    R is R1,
    addLists(T,Laux,R).

addLists([H|T],Laux,R):-number(H),
    addLists(T,Laux,R).

Answer 1

这应该有效：

add_all(L, LR):-
  foldl(add_all1, L, 0, R),
  number_codes(R, C),
  maplist([X,Y]>>(Y is X-0'0), C, LR).

add_all1(Item, R, R1):-
  (number(Item)-> R=R1 ;
    (
      atomic_list_concat(Item, N1),
      atom_number(N1, N),
      R1 is R+N
    )
  ).

样品运行：

?- add_all( [1, [2, 3], 4, 5, [6, 7, 9], 10, 11, [1, 2, 0], 6], Result).
Result = [8, 2, 2].

序言：在异类列表中添加列表

1 个答案: