Scan time savings

[PLCwannabe]

 Good evening all

 As my program is growing larger I notice the scan time increasing. I've seen it up to 20 mS. I'm using quite a few FOR loops now, seems like they are a little slow. Also wondering about rungs with multiple parallel branches, as opposed to math functions, which method increases the scan time more. Attached are a couple examples of the same control logic in different ways. I prefer the math function as takes up less space, but I don't want it to slow down the whole scan.

[BobO]

Loops are slow, but when put into tasks/programs with a yielding time slice, can break the work up across multiple scans.

Math is fast, particularly integer math.

[ATU]

Using stages to execute looping may actually yield a faster overall scan time, but the overall time of indexing the loop will be longer.  Which you choose, depends on your application.