Visual Prolong HCF code May 16, 2012 PREDICATES hcf(integer,integer,integer) CLAUSES hcf(X, Y, G) :- X = Y, G = X. hcf(X, Y, G) :- X < Y, Y1= Y-X, hcf(X, Y1, G). hcf(X, Y, G) :- X > Y, hcf(Y, X, G). GOAL hcf(17,19,G). Read more