#### Swap All Odd and Even Bits

A
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```def show_bits(before: int, after: int) -> str:
"""
>>> print(show_bits(0, 0xFFFF))
0: 00000000
65535: 1111111111111111
"""
return f"{before:>5}: {before:08b}\n{after:>5}: {after:08b}"

def swap_odd_even_bits(num: int) -> int:
"""
1. We use bitwise AND operations to separate the even bits (0, 2, 4, 6, etc.) and
odd bits (1, 3, 5, 7, etc.) in the input number.
2. We then right-shift the even bits by 1 position and left-shift the odd bits by
1 position to swap them.
3. Finally, we combine the swapped even and odd bits using a bitwise OR operation
to obtain the final result.
>>> print(show_bits(0, swap_odd_even_bits(0)))
0: 00000000
0: 00000000
>>> print(show_bits(1, swap_odd_even_bits(1)))
1: 00000001
2: 00000010
>>> print(show_bits(2, swap_odd_even_bits(2)))
2: 00000010
1: 00000001
>>> print(show_bits(3, swap_odd_even_bits(3)))
3: 00000011
3: 00000011
>>> print(show_bits(4, swap_odd_even_bits(4)))
4: 00000100
8: 00001000
>>> print(show_bits(5, swap_odd_even_bits(5)))
5: 00000101
10: 00001010
>>> print(show_bits(6, swap_odd_even_bits(6)))
6: 00000110
9: 00001001
>>> print(show_bits(23, swap_odd_even_bits(23)))
23: 00010111
43: 00101011
"""
# Get all even bits - 0xAAAAAAAA is a 32-bit number with all even bits set to 1
even_bits = num & 0xAAAAAAAA

# Get all odd bits - 0x55555555 is a 32-bit number with all odd bits set to 1
odd_bits = num & 0x55555555

# Right shift even bits and left shift odd bits and swap them
return even_bits >> 1 | odd_bits << 1

if __name__ == "__main__":
import doctest

doctest.testmod()
for i in (-1, 0, 1, 2, 3, 4, 23, 24):
print(show_bits(i, swap_odd_even_bits(i)), "\n")
```