module module1
  sub main()
    dim str as string
    str = console.readline()
    dim n as string()
    n = split(str)
    dim k as string()
    if n%2 == 0 Then
      k = 0.5
      console.printline(k)
    else
      k = (n//2)/n
      console.printline(k)
    end if 
  end sub
end module