oh wow
having worked on a circuit simulator (a SPICE clone for the Sinclair QL) in the 1980s I can tell you that you need a much, much more specialised forum than this one, good though it is.
The fact that a quick Google shows a full cmos adder netlist in "solutions to homework" at ece.ucsb.edu makes me wonder why you are asking? And if you are a lazy student? So lazy you cannot Google?
