What the different between logical operators and, or and bitwise analogs &, | in usage? Is there any difference in efficiency in various solutions?
Logical operators operate on logical values, while bitwise operators operate on integer bits. Stop thinking about performance, and use them for they're meant for.
if x and y: # logical operation
...
z = z & 0xFF # bitwise operation
Logical operators are used for booleans, since true equals 1 and false equals 0. If you use (binary) numbers other than 1 and 0, then any number that's not zero becomes a one.
Ex: int x = 5; (101 in binary) int y = 0; (0 in binary) In this case, printing x && y would print 0, because 101 was changed to 1, and 0 was kept at zero: this is the same as printing true && false, which returns false (0).
On the other hand, bitwise operators perform an operation on every single bit of the two operands (hence the term "bitwise").
Ex: int x = 5; int y = 8; printing x | y (bitwise OR) would calculate this:
000101 (5)| 1000 (8)
----------- = 1011 (11)
Meaning it would print 11.
Logical operators are these:
&& || == !
They allow you operate on logical values for example:
(true || false) // evaluates to true
(!true) // evaluates to false
Bitwise operators are these:
& | ^ ~
They allow you to operate on binary bits, like this:
~011 = 100
0101 & 0011 = 0001
来源：https://stackoverflow.com/questions/8418295/logical-vs-bitwise