To get the (i, k)th element cik of the matrix C, we take the ith row of A and kth column
of B, multiply them elementwise and take the sum of all these products In other words,
if A = [aij]m × n, B = [bjk]n × p, then the ith row of A is [ai1 ai2 ain] and the kth column of
B is 
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