Python - If/Elif statement (loops)

Question

Can someone tell me why I'm getting 4 as the outcome? Should 3 be printing instead because the code is satisfied in the If section.

a = 15
if a&5 == 0:
 print('3')
elif a% 5 == 0:
 print('4')
else:
 print('5')

• adnanmuttaleb: Because 15&5 will evaluate to 5 and 5 never equals to 0.

Answer 1

& is bitwise AND and works like this:

15 & 5

 1111
& 0101
------
 0101 != 0

Answer 2

You are comparing the bits of 15 with the bits of 5, resulting in the ones they have in common.

1111 & 101 => 101

so the result is 5, not 0.

Answer 3

The "&" operator is a Bitwise AND so in your code it is like:

1111 & 0101 = 0101

That means

15 and 5 = 5

So the first condition can not be true and you'll get 4 in output because the reminder of 15/5 is 0.

Answer 4

If you want to check LSB then you should do "and" with 1 and check the result if it's 1 then LSB is 0 else LSB is 1