The Bitwise operators is used to perform bit-level operations on the operands. The operators are first converted to bit-level and then calculation is performed on the operands. The mathematical operations such as addition , subtraction , multiplication etc. can be performed at bit-level for faster processing. In PHP, the operators that works at bit level are:
- & (Bitwise AND) : This is a binary operator i.e. it works on two operand. Bitwise AND operator in PHP takes two numbers as operands and does AND on every bit of two numbers. The result of AND is 1 only if both bits are 1.
Syntax:
$First & $Second
This will return another number whose bits are
set if both the bit of first and second are set.
Example:
Input: $First = 5, $Second = 3
Output: The bitwise & of both these value will be 1.
Explanation:
Binary representation of 5 is 0101 and 3 is 0011.
Therefore their bitwise & will be 0001 (i.e. set
if both first and second have their bit set.)
- | (Bitwise OR) : This is also binary operator i.e. works on two operand. Bitwise OR operator takes two numbers as operands and does OR on every bit of two numbers. The result of OR is 1 any of the two bits is 1.
Syntax:
$First | $Second
This will return another number whose bits are
set if either the bit of first or second are set.
Example:
Input: First = 5, Second = 3
Output: The bitwise | of both these value will be 7.
Explanation:
Binary representation of 5 is 0101 and 3 is 0011.
Therefore their bitwise | will be 0111 (i.e. set
if either first or second have their bit set.)
- ^ (Bitwise XOR ) : This is also binary operator i.e. works on two operand. This is also known as Exclusive OR operator. Bitwise XOR takes two numbers as operands and does XOR on every bit of two numbers. The result of XOR is 1 if the two bits are different.
Syntax:
$First ^ $Second
This will return another number whose bits are
set if one of the bit in first or second is
set but not both.
Example:
Input: First = 5, Second = 3
Output: The bitwise ^ of both these value will be 6.
Explanation:
Binary representation of 5 is 0101 and 3 is 0011.
Therefore their bitwise ^ will be 0110 (i.e. set
if either first or second have their bit set but
not both.)
- ~ (Bitwise NOT) : This is a unary operator i.e. works on only one operand. Bitwise NOT operator takes one number and inverts all bits of it.
Syntax:
~$number
This will invert all the bits of $number.
Example:
Input: number = 5
Output: The bitwise '~' of this number will be -6.
Explanation:
Binary representation of 5 is 0101. Therefore the
bitwise ~ of this will be 1010 (inverts all the
bits of the input number)
- << (Bitwise Left Shift) : This is a binary operator i.e. works on two operand. Bitwise Left Shift operator takes two numbers, left shifts the bits of the first operand, the second operand decides the number of places to shift.
Syntax:
$First << $Second
This will shift the bits of $First towards the
left. $Second decides the number of time the
bits will be shifted.
Example:
Input: First = 5, Second = 1
Output: The bitwise << of both these value will be 10.
Explanation:
Binary representation of 5 is 0101 . Therefore,
bitwise << will shift the bits of 5 one times
towards the left (i.e. 01010 )
Note: Bitwise left shift with one bit is equivalent to multiplication with 2.
- >> (Bitwise Right Shift) : This is also binary operator i.e. works on two operand. Bitwise Right Shift operator takes two numbers, right shifts the bits of the first operand, the second operand decides the number of places to shift.
Syntax:
$First >> $Second
This will shift the bits of $First towards the
right. $Second decides the number of time the
bits will be shifted.
Example:
Input: First = 5, Second = 1
Output: The bitwise >> of both these value will be 2.
Explanation:
Binary representation of 5 is 0101 . Therefore,
bitwise >> will shift the bits of 5 one times
towards the right(i.e. 010)
Note: Bitwise right shift with one bit is equivalent to division with 2.
Below is the implementation of Bitwise Operators in PHP:
<?php
$First = 5;
$second = 3;
$answer = $First & $second;
print_r("Bitwise & of 5 and 3 is $answer");
print_r("\n");
$answer = $First | $second;
print_r("Bitwise | of 5 and 3 is $answer");
print_r("\n");
$answer = $First ^ $second;
print_r("Bitwise ^ of 5 and 3 is $answer");
print_r("\n");
$answer = ~$First;
print_r("Bitwise ~ of 5 is $answer");
print_r("\n");
$second = 1;
$answer = $First << $second;
print_r("5 << 1 will be $answer");
print_r("\n");
$answer = $First >> $second;
print_r("5 >> 1 will be $answer");
print_r("\n");
?>
|
Output:
Bitwise & of 5 and 3 is 1
Bitwise | of 5 and 3 is 7
Bitwise ^ of 5 and 3 is 6
Bitwise ~ of 5 is -6
5 << 1 will be 10
5 >> 1 will be 2