Bitwise Operators

Bitwise Operators

Bitwise operators manipulates data at bit level. A bitwise operator operates on each bit of data. Those operators are used for testing, complementing or shifting bits to the right or left. Bitwise operators may not be applied to a float or double.

Operator	Meaning
&	Bitwise AND
|	Bitwise OR
^	Bitwise Ex-OR
~	Bitwise NOT
<<	Left shift
>>	Right shift

A bitwise AND takes two binary representations of equal length and performs the logical AND operation on each pair of corresponding bits. In each pair, the result is 1 if the first bit is 1 AND the second bit is 1. Otherwise, the result is 0.

Bitwise AND operator is "&" (ampersand). Again, this operator must not be confused with its Boolean "logical and" counterpart, which treats its operands as Boolean values, and is written "&&" (two ampersands).

   15 =  00001111 (In Binary)

20 = 00010100 (In Binary)

Bit Operation of 15 and 20
  00001111
& 00010100
  ________
  00000100  = 6 (In decimal)

A bitwise OR takes two bit patterns of equal length, and produces another one of the same length by matching up corresponding bits (the first of each; the second of each; and so on) and performing the logical inclusive OR operation on each pair of corresponding bits. In each pair, the result is 1 if the first bit is 1 OR the second bit is 1 OR both bits are 1, and otherwise the result is 0. 

Bitwise OR operator is "|" (pipe). Again, this operator must not be confused with its Boolean "logical or" counterpart, which treats its operands as Boolean values, and is written "||" (two pipes).

   15 =  00001111 (In Binary)

20 = 00010100 (In Binary)

Bit Operation of 15 and 20
  00001111
& 00010100
  ________
  000011111  = 31 (In decimal)

The bitwise NOT, or complement, is a unary operation that performs logical negation on each bit, forming the ones' complement of the given binary value. Digits which were 0 become 1, and vice versa. 

Bitwise NOT operator is "~" (Tilde), this operator must not be confused with the "logical not" operator, "!" (Exclamation point).

15 =  00001111 (In Binary)

Bitwise complement Operation of 35
! 00001111 
  ________
  11110000  

A bitwise exclusive or takes two bit patterns of equal length and performs the logical XOR operation on each pair of corresponding bits. The result in each position is 1 if the two bits are different, and 0 if they are the same.

         0101

XOR 0011

      = 0110

Bitwise XOR operator is "^" (caret).

12 = 00001100 (In Binary)
25 = 00011001 (In Binary)

Bitwise XOR Operation of 12 and 25
  00001100
^ 00011001
  ________
  00010101  = 21 (In decimal)

Left Shift Operator:

Left shift operator shifts all bits towards left by certain number of specified bits. It is denoted by <<.

Syntax:   var<< n

Here var is the variable to be shifted and n specifies the number of times to shift.

Ex:

       22<2 

      binary of 22 =   1 0 1 1 0 <<1 = 1 0 1 1 0 0 =44

                       1 0 1 1 0 0 <<1= 1 0 1 1 0 0 0=88

For every left shift operation the value becomes double.

Right Shift Operator:

Right shift operator shifts all bits towards right by certain number of specified bits. It is denoted by >>.

Syntax:   var>> n

Here var is the variable to be shifted and n specifies the number of times to shift.

Ex:

       22> 2 

      binary of 22 =   1 0 1 1 0 <<1 

                     = 0 1 0 1 1 =  11

                       0 0 1 0 1<<1= 5

For every left shift operation the value becomes half.