Lessons

JavaScript Basics

Operators in JavaScript

Conditional Statements in JavaScript

JavaScript Strings

JavaScript Arrays

JavaScript Loop

JavaScript Functions

Conclusion

JavaScript Bitwise Operators

JavaScript bitwise operators allow you to perform operations on the binary representations of numbers. They work on 32-bit numbers at the binary level, manipulating bits directly. These operators are useful for low-level operations, such as optimizing performance or working with systems that require bit-level manipulation.

How Bitwise Operators Work

Before applying bitwise operations, JavaScript converts numbers into 32-bit binary. After performing the operation, the result is converted back to a standard JavaScript number.

1. & (AND)

The & operator compares each bit of two numbers and returns 1 only if both bits are 1.

Example:

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let result = 5 & 1;  // Binary: 0101 & 0001
console.log(result); // Output: 1

Explanation:

  • 0101 (binary for 5)
  • 0001 (binary for 1)
  • 0101 & 0001 = 0001 (binary for 1)

2. | (OR)

The | operator compares each bit of two numbers and returns 1 if at least one of the bits is 1.

Example:

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let result = 5 | 1;  // Binary: 0101 | 0001
console.log(result); // Output: 5

Explanation:

  • 0101 (binary for 5)
  • 0001 (binary for 1)
  • 0101 | 0001 = 0101 (binary for 5)

3. ~ (NOT)

The ~ operator inverts all the bits of the number (turns 0s to 1s and vice versa).

Example:

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let result = ~5;  // Binary: ~0101
console.log(result); // Output: -6

Explanation:

  • 0101 (binary for 5)
  • ~0101 = 1010 (binary for -6 in two's complement representation)

4. ^ (XOR)

The ^ operator compares each bit of two numbers and returns 1 if the corresponding bits are different.

Example:

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let result = 5 ^ 1;  // Binary: 0101 ^ 0001
console.log(result); // Output: 4

Explanation:

  • 0101 (binary for 5)
  • 0001 (binary for 1)
  • 0101 ^ 0001 = 0100 (binary for 4)

5. << (Left Shift)

The << operator shifts the bits of the number to the left by the specified number of positions, filling the vacated bits with 0.

Example:

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let result = 5 << 1;  // Binary: 0101 << 1
console.log(result); // Output: 10

Explanation:

  • 0101 (binary for 5)
  • 1010 (binary for 10 after shifting left by 1)

6. >> (Right Shift)

The >> operator shifts the bits of the number to the right by the specified number of positions, filling the leftmost bits with the sign bit (0 for positive numbers, 1 for negative).

Example:

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let result = 5 >> 1;  // Binary: 0101 >> 1
console.log(result); // Output: 2

Explanation:

  • 0101 (binary for 5)
  • 0010 (binary for 2 after shifting right by 1)

7. >>> (Unsigned Right Shift)

The >>> operator shifts the bits to the right, just like >>, but fills the leftmost bits with 0 regardless of the sign.

Example:

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let result = 5 >>> 1;  // Binary: 0101 >>> 1
console.log(result); // Output: 2

Explanation:

  • 0101 (binary for 5)
  • 0010 (binary for 2 after unsigned right shift by 1)

Use Cases of Bitwise Operators

  • Low-Level Programming: Useful in tasks like bit masking, setting specific bits, or clearing bits.
  • Performance Optimization: Sometimes bitwise operations can offer faster alternatives to certain arithmetic operations.
  • Graphics and Game Development: Often used in manipulating pixel data and optimizing graphical calculations.

Frequently Asked Questions