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Bitwise operations perform calculations on binary numbers, bitwise operations on integers.
For example, 1+1=2, which is correct in decimal computation, but 1+1=10 in binary computation; If you take the binary number 100 backwards, it’s 001 instead of -100.
classification
There are seven bitwise operators, divided into two categories:
- Logical bit operators:
Bit and (&),Or (|),Bit other or (^),Not bit (~) - Shift operator:
Shift left (<<),Move right (>>),Unsigned right shift (>>>)
&The operator
The & operator (bitwise and) is used to compare two binary operands bitwise and return the result according to the conversion table shown in the following table.
&The operator |
||
|---|---|---|
| 1 | 1 | 1 |
| 1 | 0 | 0 |
| 0 | 1 | 0 |
| 0 | 0 | 0 |
In bit operations, the value 1 means true, 0 means false, and vice versa.
The bitwise and operation of 12 and 5 returns 4.
console.log(12 & 5) / / 4
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|The operator
“|” operator (or) is used to compare two binary operand bit by bit, according to the conversion table of as shown in the table and returns the result.
|The operator |
||
|---|---|---|
| 1 | 1 | 1 |
| 1 | 0 | 1 |
| 0 | 1 | 1 |
| 0 | 0 | 0 |
The bitwise or operation on 12 and 5 returns 13.
console.log(12 | 5) / / 13
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^The operator
The “^” operator (bitwise xor) is used to compare two binary operands bit by bit and returns the result according to a conversion table as shown in the table.
^The operator |
||
|---|---|---|
| 1 | 1 | 0 |
| 1 | 0 | 1 |
| 0 | 1 | 1 |
| 0 | 0 | 0 |
The bit xor operation on 12 and 5 returns 9.
console.log(12 ^ 5) / / 9
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~The operator
The “~” operator (bitwise not) is used to negate a binary operand bit by bit.
- Converts an operand to a 32-bit binary integer.
- Bit – by – bit operation.
- Converts binary inverse code to decimal floating-point number.
console.log( ~12 ) / / - 13
Copy the codeBitwise nonoperation is essentially taking the negative of a number and subtracting it by 1.
console.log( ~ 12= =12-1) // true
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