Ok, let's take an example:
137*1456

We can factorize it:
137*(1000 + 400 + 50 + 6)

To see the connection, we can convert this in form like this:
137*(1*10^3 + 4*10^2 + 5*10^1 + 6*10^0)
(where ^ means powering)

So, depending on the position of the digit in the number, we can represent it in such view (see above).

so, what we have:
137*1456=137*1*10^3 + 137*4*10^2 + 137*5*10^1 + 137*6*10^0

All you have to do now - is extract algorithm from this and code it

dear Antenka i forgot to check for new replies but anyway thank you so much for your efforts i am done , i solved it by multiplying the two arrays and putting the results in two D dimensional arrays
then adding each column elements and puttin the result in anew array
its workin properly
thank you anyway again

You're welcome and good luck with your studies!