Question

How can I take a hexadecimal number as input? I don’t mean to take an integer as input and convert it to hexadecimal, but to take a hexadecimal number as input.

Answer 1

To read a hex number from standard input and parse: gets.to_i(16). I think what you really meant to ask was how to do this:

x = gets.to_i(16)
x = x + 1
puts x.to_s(16)

Ruby defaults all parsing/printing to decimal; you have to be explicit if you want hex.