Matrix Multiplication
Write a program which reads a n×m matrix A and a m×l matrix B, and prints their product, a n×l matrix C. An element of matrix C is obtained by the following formula:
Cij = Ai1*B1j+Ai2*B2j+Ai3*B3j+...+Aim*Bmj
where aij, bij and cij are elements of A, B and C respectively.