Problem 68 Magic 5-gon ring

問題

CLPFDを用いて解いた。こういうのがCLPFDの得意分野だと思う。
作成時間1時間弱？

変数の場所

:-use_module(library(clpfd)).

main:-
	List = [A,B,C,D,E,F,G,H,I,J],
	List ins 1..10,
	all_different(List),
	A #= 10 #\/ B #= 10 #\/ C #= 10 #\/ D #= 10 #\/ E #= 10,
	maplist(#<(A),[B,C,D,E]),
	maplist(
			sum,
			[[A,F,G],[B,G,H],[C,H,I],[D,I,J],[E,J,F]],
			[#=,#=,#=,#=,#=],
			[Sum,Sum,Sum,Sum,Sum]),
	flatten([[A,F,G],[B,G,H],[C,H,I],[D,I,J],[E,J,F]],Flatten),
	setof(Flatten,label(List),Num15List),
	maplist(num_chr_recursive,Num15List,Num16List),
	write(Num15List),nl,nl,
	write(Num16List),nl,nl,
	msort(Num16List,Sorted),
	write(Sorted),nl,nl,
	last(Sorted,Last),
	write('answer:'),nl,
	write(Last).
	
num_chr_recursive([],[]):-!.
num_chr_recursive([FirstNum|RestNums],Ret):-
	!,
	num_chr_recursive(RestNums,RestChrs),
	atom_chars(FirstNum,Chrs),
	append(Chrs,RestChrs,Ret).

実行結果
[10] 25 ?- main.
***********************(解答伏せます)**********************
true.