Bitwise Operators

Bitwise operators

Bitwise operators in C, are used to work with bits and perform bit-by-bit operation.
They are equivalent to arithmetic operations like ( +, -, /, * ) the only difference is, They operates on bits instead of numbers.

The following are the bitwise operators in C:

& (bitwise AND)

This operator compares each bit of the first operand to the corresponding bit of the second operand.
If both bits are 1, the corresponding result bit is set to 1. Otherwise, the corresponding result bit is set to 0.

The syntax for the & operator is as follows:

result = operand1 & operand2;

| (bitwise OR)

This operator compares each bit of the first operand to the corresponding bit of the second operand.
If either bit is 1, the corresponding result bit is set to 1. Otherwise, the corresponding result bit is set to 0.

The syntax for the | operator is as follows:

result = operand1 | operand2;

^ (bitwise XOR)

This operator compares each bit of the first operand to the corresponding bit of the second operand.
If the bits are different, the corresponding result bit is set to 1. Otherwise, the corresponding result bit is set to 0.

The syntax for the ^ operator is as follows:

result = operand1 ^ operand2;

The truth tables for `&`, `|`, and `^`.

P	Q	P & Q	P \| Q	P ^ Q
0	0	0	0	0
0	1	0	1	1
1	1	1	1	0
1	0	0	1	1

~ (bitwise NOT)

This operator inverts all the bits of the operand.

The syntax for the ~ operator is as follows:

result = ~operand;

Bitwise left shift operator (<<)

This operator shifts the bits of the operand to the left by the specified number of positions.

The syntax for the << operator is as follows:

result = operand << shift_count;

Bitwise right shift operator (>>)

This operator shifts the bits of the operand to the right by the specified number of positions.

The syntax for the >> operator is as follows:

result = operand >> shift_count;

Examples of Bitwise operators

Example 1

In this example, we will see the use of bitwise AND, OR, XOR and NOT operators:

#include <stdio.h>

int main()
{
    int x = 5; // binary: 00101
    int y = 10; // binary: 01010

    // using & (bitwise AND) operator
    int result = x & y;
    printf("%d & %d = %d\n", x, y, result); // prints: 5 & 10 = 0

    // using | (bitwise OR) operator
    result = x | y;
    printf("%d | %d = %d\n", x, y, result); // prints: 5 | 10 = 15

    // using ^ (bitwise XOR) operator
    result = x ^ y;
    printf("%d ^ %d = %d\n", x, y, result); // prints: 5 ^ 10 = 15

    // using ~ (bitwise NOT) operator
    result = ~x;
    printf("~%d = %d\n", x, result); // prints: ~5 = -6

    return 0;
}

Output:

Output:

& 10 = 0
| 10 = 15
^ 10 = 15
~5 = -6

Explanation:

Here, we have defined two variables x and y with values 5 and 10 respectively.

In the first statement, we are using the & operator to perform bitwise AND operation on x and y. The result is 0, which is the bitwise AND of the binary representation of x and y.
In the second statement, we are using the | operator to perform bitwise OR operation on x and y. The result is 15, which is the bitwise OR of the binary representation of x and y.
In the third statement, we are using the ^ operator to perform bitwise XOR operation on x and y. The result is 15, which is the bitwise XOR of the binary representation of x and y.
In the fourth statement, we are using the ~ operator to perform bitwise NOT operation on x. The result is -6, which is the bitwise NOT of the binary representation of x.

Example 2

In this example, we will see the use of Left and Right Shift operators:

#include <stdio.h>

int main()
{
    int x = 5;  // binary: 00101
    int y = 6;  // binary: 00110

    // using << (left shift) operator
    printf("%d << 1 = %d\n", x, x << 1); // prints: 10

    // using >> (right shift) operator
    printf("%d >> 1 = %d\n", y, y >> 1); // prints: 3
    
    return 0;
}

Output:

Output:

5 << 1 = 10
6 >> 1 = 3

Explanation:

Here, we have defined two variables x and y with values 5 and 6 respectively.

In the first printf statement, we are using the << operator to perform left Shift operation on x. The result is 10.
In the first printf statement, we are using the >> operator to perform right Shift operation on y. The result is 3