How Can I 4X(4x4) Matris Multiplaction on Arduino?

Hi guys I wanna matris multiplaction 4pcs (4x4) on Arduino.How can I this?

example:

C= a b c d r s t u 8 9 10 11 24 25 26 27 40 41 42 43
e f g h X v y z x X 12 13 14 15 X 28 29 30 31 X 44 45 46 47
i j k l w 1 2 3 16 17 18 19 32 33 34 35 48 49 50 51
m n o p 4 5 6 7 20 21 22 23 36 37 38 39 52 53 54 55

C=?

How would you do it manually ?

I just googled matrix multiplication algorithm in c and got almost 600,000 hits Have you checked any of those?