我想约束一个列表的总和,但我的代码在label()
失败。参数没有充分实例化名单总和
特等:
:- use_module(library(clpfd)).
solve(L, Dim) :-
length(L, 5), % define 5 diagonals
SkipVars is Dim - 2, % to skip variables
init_sublists_above_center(L, Dim, SkipVars),
init_center(L, 2, Dim),
init_sublists_below_center(L, 3, Dim, 1),
flatten(L, FlatL),
collect_vars(FlatL, _),
writeln("list="+L),
constraint_sum(L, 38).
collect_vars([], NewL):-
all_different(NewL).
collect_vars([H|T], NewL) :-
H == 0,
collect_vars(T, NewL).
collect_vars([H|T], NewL) :-
append(NewL, [H], NewestL),
collect_vars(T, NewestL).
constraint_sum([], _).
constraint_sum([H|T], Sum) :-
writeln(H),
label(H),
sum_list(H, Sum),
constraint_sum(T, Sum).
init_sublists_above_center([H|T], Dim, SkipVars) :-
length(H, Dim),
init_zeroes(H, SkipVars),
NewSkipVars is SkipVars + 1,
NewSkipVars =< Dim,
init_sublists_above_center(T, Dim, NewSkipVars).
init_sublists_above_center(_, _, _).
init_sublists_below_center(_, _, Dim, Fill) :-
End is Dim - 2,
Fill == End.
init_sublists_below_center([H|T], ToSkip, Dim, Fill) :-
ToSkip == 0,
length(H, Dim),
init_zeroes_start(H, Fill),
NewFill is Fill + 1,
init_sublists_below_center(T, 0, Dim, NewFill).
init_sublists_below_center([_|T], ToSkip, Dim, Fill) :-
NewToSkip is ToSkip - 1,
init_sublists_below_center(T, NewToSkip, Dim, Fill).
init_center(_, ToSkip, _) :-
ToSkip == -1.
init_center([H|_], ToSkip, Dim) :-
ToSkip == 0,
length(H, Dim),
init_center(_, -1, _).
init_center([_|T], ToSkip, Dim) :-
NewToSkip is ToSkip - 1,
init_center(T, NewToSkip, Dim).
init_zeroes([], _).
init_zeroes([H|T], Fill) :-
Fill == 0,
H is 0,
init_zeroes(T, Fill).
init_zeroes([_|T], Fill) :-
NewFill is Fill - 1,
init_zeroes(T, NewFill).
init_zeroes_start(_, Fill) :-
Fill == 0.
init_zeroes_start([H|T], Fill) :-
H is 0,
NewFill is Fill - 1,
init_zeroes_start(T, NewFill).
输出:
7 ?- solve(L, 5).
list= + [[_G15351,_G15407,_G15466,0,0],[_G15525,_G15584,_G15643,_G15702,0],[_G15761,_G15820,_G15879,_G15938,_G15997],[0,_G16056,_G16115,_G16174,_G16233],[0,0,_G16292,_G16351,_G16410]]
[_G15351,_G15407,_G15466,0,0]
ERROR: Arguments are not sufficiently instantiated
任何想法吗?
编辑:
运行调试后:,我认为错误是里面label()
,在这一点上:
finite_domain(Var) :-
( fd_get(Var, Dom, _) ->
( domain_infimum(Dom, n(_)), domain_supremum(Dom, n(_)) -> true
; instantiation_error(Var)
)
; integer(Var) -> true
; must_be(integer, Var)
).
一个想法是运行跟踪然后再次尝试您的查询。键入'trace.'然后执行查询。每个步骤都会详细显示,直到您遇到问题。它将查明问题所在。 – lurker
谢谢潜伏者,从现在开始我会记住这一点! – gsamaras
这是一个方便的工具。有时候,你需要提供一个非常简单的例子,尽管如此,或者你可能整天都在那里跟踪! – lurker