C Programming - Bitwise Operators - Discussion

Discussion Forum : Bitwise Operators - Find Output of Program (Q.No. 2)
2.
If an unsigned int is 2 bytes wide then, What will be the output of the program ?
#include<stdio.h>

int main()
{
    unsigned int m = 32;
    printf("%x\n", ~m);
    return 0;
}
ffff
0000
ffdf
ddfd
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
35 comments Page 1 of 4.

Mallesh said:   3 months ago
#include<stdio.h>

int main()
{
unsigned int m = 32;
printf("%x\n", ~m);
return 0;
}

Ans:-
1's complement: Inverting the bits ( all 1s to 0s and all 0s to 1s).
Binary of 32(2 byte) : 0000 0000 0010 0000.
Representing -32: Make it 1's complement then,
1s complement of 32(2byte) : 1111 1111 1101 1111.

This is the result: ffdf

Meghana k said:   2 years ago
Thank you it was helpful.

Nikhil tekade said:   3 years ago
Negative numbers are treated with 2's complement method.

1's complement: Inverting the bits ( all 1s to 0s and all 0s to 1s).
2's complement: Adding 1 to the result of 1's complement.

Binary of 32(2byte) : 0000 0000 0010 0000.
Representing -32:

1s complement of 32(2byte) : 1111 1111 1101 1111.
Adding 1 to 1's comp. result : 1111 1111 1110 0000.
Hexadecimal: f f df.
(5)

Zakar said:   7 years ago
32 complement = 1111 1111 1101 1111.

In hexadecimal f f d f.
(3)

Jishan said:   8 years ago
Negative numbers are treated with 2's complement method.

1's complement: Inverting the bits ( all 1s to 0s and all 0s to 1s).
2's complement: Adding 1 to the result of 1's complement.

Binary of 32(2byte) : 0000 0000 0010 0000.
Representing -32:
1s complement of 32(2byte) : 1111 1111 1101 1111.
Adding 1 to 1's comp. result : 1111 1111 1110 0000.
Hexadecimal : f f e 0.

This is not given in the option, checked on Ubuntu machine.
(3)

Selvameenal C said:   8 years ago
Yes, there is m=32=0000 0000 0010 0000;
~m(1s complement)= 1111 1111 1101 1111;
Thus answer : ffdf.
(3)

Anirudh sharma said:   9 years ago
~ 32 = (32 + 1) *-1.
- 33
33 = 0000 0000 0010 0001.
2complemnt is:

1111 1111 1101 1111
f f d f

So the answer is f f d f.
(7)

Shreya said:   10 years ago
32 = 2^5 = 2*2*2*2*2. So here 2^5 bit is 1 = 0000 0000 0010 0000.

But what they have asked is ~m so = 1111 1111 1101 1111.

Vinod said:   1 decade ago
"%x" represents hexadecimal. How to print a number in binary form?
(1)

Mounika kursing said:   1 decade ago
32 16 8 4 2 1

2^5 2^4 2^3 2^2 2^1 2^0

0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0
1 1 1 1 1 1 1 1 1 1 0 1 1 1 1 1
f f d f

We want 32, So keep 1 at 32 all other 0.
For negation replace 0's with 1's.


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