Advanced Programming Techniques in C/

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The Utility of the AND Bitwise Operator

The Utility of the AND Bitwise Operator

Get introduced to the utility of & operator.

We'll cover the following...

The AND & operator is used to:

  • Check whether a bit is on or off
  • Switch off a particular bit

Check whether a bit is on or off

See the code given below!

C
#include <stdio.h> 
# define BV(x) ( 1 << x) 
int main( ) 
{
  // Declare variables
	unsigned char n ; 
	unsigned int val ;
	n = 120;
  // Check 3rd bit is on or off
	if ( ( n & BV(3) ) == BV(3) ) 
	{
    // Display 3rd bit is on
		printf( "3rd bit is on\n" ) ; 
	}
  // Display 3rd bit is off
	else 
		printf ( "3rd bit is off\n" ) ;
}

To check whether the 3rd3^{rd} bit is on or off, we need to, first, select the appropriate mask value. In the mask value, only the bit at that particular place should be 1. Since we want to check whether the 3rd3^{rd} ...