Need help to write Routine

Hi Gurus,

I need your urgent help on one requirement. I have to write a routine and the requirement is to bring data for K.F. "B" via comparing Materials between 0Material and 0MAT_UNITS.

0Material is already present in my flow and being loaded from DSO1 to DSO2 but 0MAT_UNITS not present. So I have to use a look-up on it using Materials from 0Material.

Materials has to be taken from 0Material and using condition as Observer-A(active)  have to match with the materials of 0MAT_UNITS. If the material is present in 0MAT_UNITS with observer 'A' then take the Denominator and Numerator value for that material and produce a conversion factor for that material i.e. (Denominator/Numerator).

Now this factor need to be multiply with a K.F. "A" (already present in my DSO1) and assign the value to K.F. "B" as output (DSO2).

So pls guide me how should I code it in routine and which type of routine should I prefer.

Any effective help will be highly appreciated!!!!