Monitor times spent in a matrix

I have homework, 2 parts

1. Initialize 2 square arrays (dynamically), then multiple them and save the result in third array. (I have done this part using list queue)

2. Monitor times spent in the matrix multiplication part. ??????

(i need this part)

Then test the code many times each time with different array size and monitor the time, so i can analyze the multiplication time as a function of array size.

Am working on windows xp / C++

I need time in microseconds

Thz

How can I do it using Linux?

Someone told me it is easier to solve this problem using Linux (He forget the correct command ) , dose anyone know How can I do that? ????

Rajaa