Write a C program to input any number from user and check whether the Least Significant Bit (LSB) of the given number is set (1) or not (0). How to check whether the least significant bit of a number is set or unset using bitwise operator in C programming. C program to get the status of least significant bit of a number.

**Example**

**Input**

Input number: 11

**Output**

Least Significant Bit of 11 is set (1).

Read more – Program to check Most Significant Bit (MSB) of a number.

## Required knowledge

Bitwise operators, Data types, Variables and Expressions, Basic input/output, If else

## Logic to check Least Significant Bit (LSB) of a number

We use Bitwise AND `&`

operator to check status of any bit. Bitwise AND `&`

operator evaluate each bit of the resultant value as `1`, if corresponding bits of both operands are `1`.

To check LSB of a number we need to perform bitwise ANDing. The bitwise AND operation `number & 1`

will evaluate to `1` if LSB of number is set i.e. `1` otherwise evaluates to `0`.

As you can see in above image `12 & 1`

evaluate to `0`. Since, LSB of `12` is `0`. Whereas, `15 & 1`

evaluate to `1` since LSB of `15` is `1`.

## Program to check Least Significant Bit (LSB) of a number

```
/**
* C program to check Least Significant Bit (LSB) of a number using bitwise operator
*/
#include <stdio.h>
int main()
{
int num;
/* Input number from user */
printf("Enter any number: ");
scanf("%d", &num);
/* If (num & 1) evaluates to 1 */
if(num & 1)
printf("LSB of %d is set (1).", num);
else
printf("LSB of %d is unset (0).", num);
return 0;
}
```

**Important note: ** The statement `if(num & 1)`

is equivalent to `if(num & 1 == 1)`

.

Output

Enter any number: 11 LSB of 11 is set (1).

Happy coding ðŸ˜‰

### Recommended posts

- Bitwise operator programming exercises index.
- C program to get highest set bit of a number.
- C program to get lowest set bit of a number.
- C program to count trailing zeros in a binary number.
- C program to count leading zeros in a binary number.
- C program to flip bits of a binary number using bitwise operator.