eq(f0(A),1,[f1(A,B,C),loop_cont_f1(C)],[B=0]). eq(f0(A),1,[f1(A,B,C)],[B=1]). eq(f1(A,B,C),1,[f1(0,B,C)],[A>=0]). eq(f1(A,B,A),0,[],[B=1]).