C Bitwise AND Operator

In C, the Bitwise AND & operator is used to perform a bitwise AND operation between two integers at the binary level. It compares each bit of both operands and returns 1 if both bits are 1; otherwise, it returns 0.

The Bitwise AND operator is commonly used for bit masking and checking specific bits.

Syntax of the Bitwise AND Operator

The syntax to use the Bitwise AND operator is:

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result = operand1 & operand2;

Explanation:

  1. operand1: The first integer operand.
  2. &: The Bitwise AND operator.
  3. operand2: The second integer operand.
  4. result: The result of the bitwise AND operation. Each bit in result is 1 if both corresponding bits in operand1 and operand2 are 1, otherwise, it is 0.

Examples of the Bitwise AND Operator

1. Using Bitwise AND on Two Integers

In this example, we will apply the Bitwise AND & operator on two integers and display the result.

main.c

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#include <stdio.h>

int main() {
    int a = 5, b = 3;
    int result = a & b;

    printf("Bitwise AND of %d and %d is %d\n", a, b, result);

    return 0;
}

Explanation:

  1. The variables a and b are initialized with values 5 (0101 in binary) and 3 (0011 in binary).
  2. The Bitwise AND operation a & b compares each bit:
   0101 (5)
 & 0011 (3)  
 --------
   0001 (1)
  1. The result 1 (0001 in binary) is stored in result and printed.

Output:

Bitwise AND of 5 and 3 is 1

2. Checking If a Number is Even Using Bitwise AND

In this example, we will use the Bitwise AND & operator to check if a number is even.

main.c

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#include <stdio.h>

int main() {
    int num = 10;

    if (num & 1) {
        printf("%d is Odd\n", num);
    } else {
        printf("%d is Even\n", num);
    }

    return 0;
}

Explanation:

  1. The integer variable num is assigned a value of 10.
  2. The expression num & 1 checks the least significant bit (LSB) of num.
  3. Since 10 in binary is 1010, performing 10 & 1 results in 0 (even number).
  4. If the result is 0, the number is even; otherwise, it is odd.

Output:

10 is Even

3. Bitwise AND for Bit Masking

In this example, we will use the Bitwise AND & operator to check if a specific bit in a number is set.

main.c

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#include <stdio.h>

int main() {
    int num = 42;  // Binary: 101010
    int mask = 8;  // Binary: 001000

    if (num & mask) {
        printf("The 4th bit is set.\n");
    } else {
        printf("The 4th bit is not set.\n");
    }

    return 0;
}

Explanation:

  1. The integer variable num is assigned the value 42 (binary: 101010).
  2. The mask variable is set to 8 (binary: 001000), which checks the 4th bit.
  3. The bitwise AND operation num & mask checks if the 4th bit of num is set.
  4. If the result is nonzero, the bit is set; otherwise, it is not set.

Output:

The 4th bit is set.

Conclusion

In this tutorial, we covered the Bitwise AND & operator in C. Important points to remember are:

  1. The Bitwise AND & operator compares each bit of two operands.
  2. It returns 1 where both bits are 1, otherwise 0.
  3. Common use cases include bitwise operations, even/odd checking, and bit masking.

The Bitwise AND & operator is essential for low-level programming and bit manipulation.