Matrix Multiplication

1. Suppose C = A * B, do you remember how to obtain an entry c[i][j]? To find the summation of multiplication of a[i][k]*b[k][j], you may need to iterate through a for-loop controlled by variable k.
   So, totally you may need 3 layers of for-loop to perform the matrix multiplication.
2. The input would be 3 rows of matrix A, and then 3 rows of matrix B, as show below. Note that there is no blank lines to separate these two matrices.

   
   1 2 3
   4 5 6
   7 8 9
   1 4 7
   2 5 8
   3 6 9
   
   

3. You may need std::setw() to right-justify entries in a matrix, if you want to obatin an output as follows:

   
    14  32  50
    32  77 122
    50 122 194