C -- bit operation

1、 Bit operators and bit operations

Operator	meaning	Operator	meaning
&	Bitwise AND	~	Take the opposite
|	Press bit or	<<	Move left
^	Bitwise XOR	>>	Move right

• priority ：~–><<、>>–>&、^、|
• Take the opposite (~) skill ：
  1. The positive result is -( Positive numbers +1)
  2. The negative result is -( negative +1)
  3. `x=-(x+1)
• Shift left operator (<<)
  1. Used to put all bits of a number in binary Move left a few places
  2. Shift all binary numbers to the left n position , Right side mend 0
  3. The rules ： Move left n Multiply by ₂n
• Shift right operator (>>)
  1. It is used to put all the binaries of a number Move a few bits to the right
  2. Shift all binary numbers to the right n by , Discard at the end of the right end
  3. The rules ： Move left n Bits divided by ₂n

2、 Compound bit operators

1. type ：&=、|=、^=、<<=、>>=

2. for example ：

   a&=b Equivalent to a=a&b
   a>>=2 Equivalent to a=a>>2
   

3、 Bit operation features

	0	1
Bitwise &	Zero clearing	unchanged
Bitwise |	unchanged	Set up 1
Bitwise ^	unchanged	Flip