Chapter 4.5, Problem 80E

Problems $77\text{-}80$ refer to the encoding matrix

$A=\left[\begin{array}{cc}1& 2\\ 1& 3\end{array}\right]$

Cryptography. The following message was encoded with matrix A. Decode this message:

$\text{36 44 5 5 38 56 55 75 18 23 56 75 22 33 37 55 27 40 53 79 59 81}$