Bitwise Operators in C

Operators which are used to perform bit-level operations or bitwise manipulations in C programming are called bitwise operators.

1. Bitwise AND (&)
2. Bitwise OR (|)
3. Bitwise XOR or Bitwise exclusive OR (^)
4. Bitwise complement or Bitwise NOT (~)
5. Bitwise Left Shift (<<)
6. Bitwise Right Shift (>>)

OPERATOR	DESCRIPTION
&	Bitwise AND
|	Bitwise OR
^	Bitwise XOR or Bitwise exclusive OR
~	Bitwise complement or Bitwise NOT
<<	Bitwise Left Shift
>>	Bitwise Right Shift

Bitwise AND operator is denoted by the single ampersand sign (&). It takes two bits at a time and performs AND operation.It is a binary operator takes two operands.The result of bitwise AND is 1 if both bits are 1; otherwise, the output would be 0.

Let us suppose the bitwise AND operation of two integers num1=6 and num2=4.
The binary representation of above two variables is:
num1=00000110
num2=00000100

Bit Operation of 6 and 4
   00000110
& 00000100

---

   00000100 = 4 (In decimal)

Code for Bitwise AND(&)

#include <stdio.h>
void main()
{
int num1 = 6, num2 = 4;
printf("Bitwise AND result is %d", num1&num2);
}

Bitwise OR operator is denoted by the single verticle sign (|). It takes two bits at a time and performs OR operation.It is a binary operator takes two operands.The result of bitwise OR is 0 if both bits are 0; otherwise, the output would be 1.

Let us suppose the bitwise OR operation of two integers num1=6 and num2=4.
The binary representation of above two variables is:
num1=00000110
num2=00000100

Bit Operation of 6 and 4
   00000110
| 00000100

---

   00000110 = 6 (In decimal)

Code for Bitwise OR(|)

#include <stdio.h>
void main()
{
int num1 = 6, num2 = 4;
printf("Bitwise OR result is %d", num1|num2);
}

Bitwise OR operator is denoted by (^) symbol. It is a binary operator takes two operands.The result of bitwise XOR operator is 1 if the corresponding bits of two operands are opposite.

Let us suppose the bitwise XOR operation of two integers num1=6 and num2=4.
The binary representation of above two variables is:
num1=00000110
num2=00000100

Bit Operation of 6 and 4
   00000110
^ 00000100

---

   00000010 = 2 (In decimal)

Code for Bitwise XOR(|)

#include <stdio.h>
void main()
{
int num1 = 6, num2 = 4;
printf("Bitwise XOR result is %d", num1^num2);
}

Bitwise complement operator is an unary operator (works on only one operand).It is also known as one's complement operator. It changes 1 to 0 and 0 to 1. It is denoted by tilde(~) symbol.

Let us suppose the bitwise complement operation of one integer num1=6 .
The binary representation of above two variables is:
num1=00000110
Bit Operation of 6
~00000110

---

    11111001 = 249 (In decimal)
The bitwise complement of 6 (~6) is -7 instead of 249,why?
For any integer number n, bitwise complement of n will be -(n+1). To understand this, you should have the knowledge of 2's complement.

2's Complement

Two's complement is an operation on binary numbers. The 2's complement of a number is equal to the complement of that number plus 1. For example:

Decimal	Binary	2's Complement
0	00000000	-(11111111+1) = -00000000 = -0(decimal)
1	00000001	-(11111110+1) = -11111111 = -256(decimal)
12	00001100	-(11110011+1) = -11110100 = -244(decimal)
220	11011100	-(00100011+1) = -00100100 = -36(decimal)

Code for Bitwise NOT(~)

#include <stdio.h>
void main()
{
int num1= 6;
printf("Bitwise NOT result is %d", ~num1);
}

Left shift operator is an operator that shifts the number of bits to the left-side.The bit positions that have been vacated by the left shift operator are filled with 0. The left shift operator is denoted by << symbol.
The left shift (<<) operator takes two numbers, left shifts the bits of the first operand, the second operand decides the number of places to shift.

Let us suppose the bitwise left shift (<<) operation of num1=6.
The binary representation of num1 variable is:
num1=00000110
Bit Operation of 6
If we want to left-shift the above representation by 2, then the statement would be: 
num1 << 2;
00000110<<2 = 00001100  

Code for Bitwise Left Shift(<<)

#include <stdio.h>
void main()
{
int num1 = 6;
printf("Bitwise left shift << result is %d", num1<<2);
}

Right shift operator is an operator that shifts the number of bits to the right-side.The bit positions that have been vacated by the right shift operator are filled with 0. The right shift operator is denoted by >> symbol.
The right shift (>>) operator takes two numbers, right shifts the bits of the first operand, the second operand decides the number of places to shift.

Let us suppose the bitwise right shift (>>) operation of num1=6.
The binary representation of num1 variable is:
num1=00000110
Bit Operation of 6
If we want to right-shift the above representation by 2, then the statement would be: 
num1 >> 2;
00000110>>2 = 00000001  

Code for Bitwise Right Shift(>>)

#include <stdio.h>
void main()
{
int num1 = 6;
printf("Bitwise right shift >> result is %d", num1>>2);
}