option(guard_simplification,on).
option(mode,sum(+,?)).
option(type_definition,type(list(X), [ [], [X | list(X)]])).
option(type_declaration,sum(list(int),int)).


:- constraints sum/2.

sum([],S) <=> S=0.
sum([A|R],S) <=> sum(R,T), S is A+T.

sum_prolog([],S) :- S=0.
sum_prolog([A|R],S) :- sum_prolog(R,T), S is A+T.





go :- go(10000,500).
go(Count,N):-
	measure(main_prolog(Count,N), true, Utime,Gtime,System),
	write(bench(sum_prolog,Count-N,Utime,Gtime,System)), write('.'),nl,fail.
go(Count,N):-
	measure(main(Count,N), true, Utime,Gtime,System),
	write(bench(sum_CHR,Count-N,Utime,Gtime,System)), write('.'),nl,fail.


makelist(0,[]).
makelist(N,[1|R]) :- N>0, N1 is N-1, makelist(N1,R).

main(N,0).
main(N,K):- K>0,
	makelist(N,L),
	(sum(L,S),fail;K1 is K-1,main(N,K1)).
	
main_prolog(N,0).
main_prolog(N,K):- K>0,
	makelist(N,L),
	(sum_prolog(L,S),fail;K1 is K-1,main_prolog(N,K1)).