%Source: http://colin.barker.pagesperso-orange.fr/sands.htm
%query:timeslist(g,f).
/* timeslist(Is,Prod) is true if Prod is the product of the list Is.       */
timeslist([I|Is],Prod):-timeslist(Is,I,Prod).

timeslist([],Prod,Prod).
timeslist([I|Is],Temp,Prod):-Temp1 is Temp*I, timeslist(Is,Temp1,Prod).