Question

For instance : -78_base10 on 8 bits is 0xB2

The pseudo-algorithm says : “-A =/A+1”

For instance :

• -78 => 78 => 01001110
• Then apply ‘bar’ : 01001110 => 10110001
• Then ‘+1’ : 10110001 + 1 = 10110010
• convert in hexa : 0xB2

How to get the result nicely in Ruby (with or without this ‘algorithm’).

Answer 1

How about something like

def signed_int_to_hex(n)
  "0x%X" % (n % 2 ** 8)
end

signed_int_to_hex(-78) #=> "0xB2"