C Programming - Bitwise Operators - Discussion

As @Bheemraj said 24>>4 =1. I don't know how?

As far as I know, it should be 24=0001 1000 >> 1000 0001=129 by right shifting 4 times.

And what is the concept of multiplying by 1, 2, 4, 8 and dividing by 2, 4, 8, 6.

Also I don't know how does this happens.

1. Fill with 1s in the left side for right shift for negative numbers.
2. Fill with 0s in the right side for left shift for negative numbers.
3. Fill with 0s in the left side for right shift for positive numbers.
4. Fill with 0s in the right side for left shift for positive numbers.

I only know to fill vacant places by 0 not by 1. If anyone knows answers please explain.

Thank you.

@New coder.

x = 24; /* 0001 1000 */
y = x>>4 ;
y = 1; /* 0000 0001*/ the two 1s shifted 4 bits so one of them became out the number and the another one which you see now.

I don't understand that too!

1. Fill with 1's on the left side for a right shift for negative numbers.
2. Fill with 0's on the right side for a left shift for negative numbers.
3. Fill with 0's on the left side for a right shift for positive numbers.
4. Fill with 0's on the right side for a left shift for positive numbers.

>> shifts the bits in right direction, which means number is divided by 2,4,8,16,.... e.g. 24>>4 gives output 1.

In case of left shift operator, it will multiply the no. by 1,2,4,8,.. e.g. 17<<2 will give 68.

Now at last , ~ this operator finds 1's(one's) complement of any number.

@fool coder.

>> shifts the bits in right direction, which means number is divided by 2, 4, 8, 16.

Example: 24>>4 gives output 1.

In case of left shift operator, it will multiply the no. by 1, 2, 4, 8. E.g. 17<<2 will give 68.

Can you explain more about negative numbers?

-1>>1
-1= for negative value use 2's complement.

-1 -->0000 0000 0000 0001
1's-->1111 1111 1111 1110
2's--> 1
-------------------
1111 1111 1111 1111

And the -1 is right shifting once.

Answer : 0111 1111 1111 1111--->7FFF.

@Mrutyunjay patil.

-4= 0000 0000 0000 0100.
1's ->1111 1111 1111 1011.
2's->adding 1.
1111 1111 1111 1100.

By left shifting 0 as -4<<2,we get.
1111 1111 1111 0000.
Since,
fff0.

Just a small change in the pgm gave me different answer. Can any1 explain the concept of that.
#include<stdio.h>
int main()
{
unsigned int i=-1;
printf("%x\n",i>>1);
}

Result was 7fff

Please give me the output of this question with an explanation.

#include<stdio.h>
int main()
{
printf("%x\n", -4<<2);
return 0;
}

A. fff0
B. 0
C. ffff
D. Error

How we convert numbers into letters and letters into numbers by using hexadecimal system.

Example:1111's are indicated with f how it is possible.

What is o/p ?

#include<stdio.h>

int main()
{
printf("%x\n", -1>>1);
return 0;
}