NewGuyinTown
Is it safe to say a ripplecarry adder has O(n) and the lookahead carry adder has O(1)?

A Question for Electrical and Computer EngineersNewGuyinTown
Is it safe to say a ripplecarry adder has O(n) and the lookahead carry adder has O(1)?
Esch
While it's marginally safe to say that a ripplecarry adder has O(n) complexity, I don't think you can say that a carrylookahead adder has O(1). As you increase n, the number of gates you require increases tremendously (by a factor of O(n^2), actually) as well as (more importantly) the number of inputs to your gates (especially the OR gates), which ends up making them much slower.
I'm not sure what the performance analysis would be off the top of my head, but it's surely more than constant time. Related topics
