Bitwise Operators

Bitwise operator works on bits and perform bit by bit operation. The truth tables for &, |, and ^ are as follows:

pqp & qp | qp ^ q
00000
01011
11110
10011

Assume if A = 60; and B = 13; Now in binary format they will be as follows:

A = 0011 1100

B = 0000 1101

-----------------

A&B = 0000 1100

A|B = 0011 1101

A^B = 0011 0001

~A = 1100 0011

The Bitwise operators supported by C language are listed in the following table. Assume variable A holds 60 and variable B holds 13 then:

OperatorDescriptionExample
&Binary AND Operator copies a bit to the result if it exists in both operands. (A & B) will give 12 which is 0000 1100
|Binary OR Operator copies a bit if it exists in either operand. (A | B) will give 61 which is 0011 1101
^Binary XOR Operator copies the bit if it is set in one operand but not both. (A ^ B) will give 49 which is 0011 0001
~Binary Ones Complement Operator is unary and has the effect of 'flipping' bits. (~A ) will give -60 which is 1100 0011
<<Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand. A << 2 will give 240 which is 1111 0000
>>Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand. A >> 2 will give 15 which is 0000 1111


Example
Try following example to understand all the bitwise operators available in C programming language:

#include <stdio.h>

main
()
{

unsigned int a = 60; /* 60 = 0011 1100 */
unsigned int b = 13; /* 13 = 0000 1101 */
int c = 0;

c
= a & b; /* 12 = 0000 1100 */
printf
("Line 1 - Value of c is %d\n", c );

c
= a | b; /* 61 = 0011 1101 */
printf
("Line 2 - Value of c is %d\n", c );

c
= a ^ b; /* 49 = 0011 0001 */
printf
("Line 3 - Value of c is %d\n", c );

c
= ~a; /*-61 = 1100 0011 */
printf
("Line 4 - Value of c is %d\n", c );

c
= a << 2; /* 240 = 1111 0000 */
printf
("Line 5 - Value of c is %d\n", c );

c
= a >> 2; /* 15 = 0000 1111 */
printf
("Line 6 - Value of c is %d\n", c );
}

When you compile and execute the above program it produces following result:

Line 1 - Value of c is 12
Line 2 - Value of c is 61
Line 3 - Value of c is 49
Line 4 - Value of c is -61
Line 5 - Value of c is 240
Line 6 - Value of c is 15


Post a Comment