Write a function that accepts two square (
NxN) matrices (two dimensional arrays), and returns the product of the two. Only square matrices will be given.
How to multiply two square matrices:
We are given two matrices, A and B, of size 2×2 (note: tests are not limited to 2×2). Matrix C, the solution, will be equal to the product of A and B. To fill in cell
 of matrix C, you need to compute:
A * B + A * B.
More general: To fill in cell
[n][m] of matrix C, you need to first multiply the elements in the nth row of matrix A by the elements in the mth column of matrix B, then take the sum of all those products. This will give you the value for cell
[m][n] in matrix C.
Link to Wikipedia explaining matrix multiplication (look at the square matrix example): http://en.wikipedia.org/wiki/Matrix_multiplication
A more visual explanation of matrix multiplication: http://matrixmultiplication.xyz
The solution in Java code
Test cases to validate our solution