ez:=proc(): print(`EvalCFg(A,B):`): end:


#Corrected after class
#EvalCFg(A,B): evaluates the non-simple continued with numerators B and denominators A s given in Chrystal's book p. 512, Eq. (1)
EvalCFg:=proc(A,B) local A1,B1,x:
if not (type(A,list) and nops(A)>0) then
  RETURN(FAIL):
fi:

if not (type(B,list) and nops(B)>0) then
  RETURN(FAIL):
fi:

if nops(A)<>nops(B) then
  RETURN(FAIL):
fi:

if nops(A)=1 then
  RETURN(B[1]/A[1]):
fi:

A1:=[op(2..nops(A),A)]:

B1:=[op(2..nops(B),B)]:

x:=EvalCFg(A1,B1):

normal(B[1]/(A[1]+x)):
end: