How to come up with a matrix structure?

Question

I was trying to make a matrix structure myself, but it didn't work.
Especially when I try to define operators or define arrays with not previously mentioned sizes(I tried vectors too.)
I'm using c++ and want to make this structure to be able to define matrixes with a given size(n, m) and do matrix multiplications.
Sites and weblogs didn't help me very much.
Can you help me or introduce me a good source to learn about structures and class and defining operators?
Thank you very much:)

Answer 1

first you are not very clear with your question and secondly what IDE are you using? Turbo C++ and other older versions don't support variable arrays.