Thread: enumeration

Hi!

Can anyone explain to me why is the range of "enum e2 { a=3, b=9 };" equal to 0:15?

This are the examples from the Stroustrup book:

Code:

enum e1 { dark, light }; // range 0:1
enum e2 { a=3, b=9 }; // range 0:15
enum e3 { min=-10, max=1000000 }; // range -1048576:1048575
enum flag {x=1, y=2, z=4, e=8 }; // range 0:15

The only sence to me is e1. dark has value 0 and light has value 1. For others I have no idea.
What does that range mean anyway?

I second Salem on this one.


enum e1 { dark, light }; // range 0:1

dark = 0
light = 1

0 - 1


enum e2 { a=3, b=9 }; // range 0:15

a = 3 / 0011
b = 9 / 1001^

0000 - 1111
0 - 15


enum e3 { min=-10, max=1000000 }; // range -1048576:1048575

max = 1000000 / F4240

FFFFF (16) = 1048575 (10)


enum flag {x=1, y=2, z=4, e=8 }; // range 0:15

x = 1 / 0001
y = 2 / 0010
z = 4 / 0100
e = 8 / 1000

0000 - 1111
0 - 15