convert2Roman 17 == "XVII"
convert2Roman 19 == "IXX"

decodeRoman "XVII" == 17
decodeRoman "IXX" == 19

codeCaesar "Fun" 3 == "Ixq"
decodeCaesar "Ixq" (-3) == "Fun"

concatSpecial [1,2,3] [4,5] 2 == [1,4,5,2,3]
concatSpecial [1,2,3] [4,5] 1 == [4,5,1,2,3]