Detailed explanation of PHP bit operators

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Bit Operator

The bit operator refers to the binary bit from the low bit Perform operations after aligning to the high bit.

##887a7712dda16e147f6d179d5c9c66e0>Shift right

Symbol	Function	Example	Personal understanding
&	bitwise AND	$m & $n	All 1’s are 1, otherwise 0
|	Bitwise OR	$m | $n	All 0s are 0, and 1 is 1
^	Bitwise XOR	$m | $n	is different from 1 , the same as 0
~	bitwise inversion	~$m
		$m >> $n

##&operator

<?php
$m = 1;
$n = 2;
$mn = $m & $n;
echo $mn;

The operation result is 0

Explanation: Convert 1 and 2 into binary respectively as

00000001

00000010

In the process of bitwise AND, all 1s are 1, The comparison result is 00000000, so the output is 0

|Operator

<?php
$m = 1;
$n = 2;
$mn = $m | $n;
echo $mn;

The operation result is 3. Similarly, it is converted into the binary number

00000001# as above

##00000010

In the process of bitwise OR, if 1 is 1 and all 0 is 0, the result is 00000011, so the output is 3

^ operator

<?php
$m = 1;
$n = 2;
$mn = $m ^ $n;
echo $mn;

The running result is 3. Similarly, it is converted into the above binary number

00000001

00000010

In the process of bitwise OR , the difference is 1, the same is 0, so the result is 00000011, and 3 is output.

~Operator

<?php
$m = 2;
$m1 = ~$m;
echo $m1;

The operation result is -3, which is thought-provoking.

Note: In computers, negative numbers are expressed in the complement form of their positive values.

1: The 32-bit original code of 2 is 0000 0000 0000 0000 0000 0000 0000 0010

2: The bitwise inversion is 1111 1111 1111 1111 1111 1111 1111 1101

Since the first number is 1 and the sign bit is 1, it is a negative number. Therefore, the complement form of its positive value is expressed as: (the sign bit remains unchanged, bitwise inversion, and 1 is added at the end)

1000 0000 0000 0000 0000 0000 0000 0011

So the output is -3

aadd5699ea49e0a4f2bfd9ad5921d7f6>Operator

Shift one position to the right, similar to the << operator, except that this is a right shift, which is not done here. Too much explanation.

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