Questions and answers for exam Preparation

MCQs

Total Questions : 35 | Page 2 of 4 pages

Question 11.

Bitwise & can be used to check if a bit in number is set or not.

True
False

Discuss Question

Answer: Option A. -> True

Question 12.

Left shifting a number by 1 is always equivalent to multiplying it by 2.

True
False

Discuss Question

Answer: Option A. -> True

0001 => 1
0010 => 2
0100 => 4
1000 => 8

Question 13.

In the statement expression1 >> expression2. if expression1 is a signed integer with

its leftmost bit set to 1 then on right shifting it the result of the statement will vary from

computer to computer

True
False

Discuss Question

Answer: Option A. -> True

Question 14.

Bitwise & can be used to check if more than one bit in a number is on.

True
False

Discuss Question

Answer: Option A. -> True

Question 15.

Bitwise & and | are unary operators

True
False

Discuss Question

Answer: Option B. -> False

Bitwise & and | are not unary operators only bitwise ! is unary operator.

Question 16.

Which of the following statements are correct about the program?

#include<stdio.h>
int main()
{
unsigned int m[] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80};
unsigned char n, i;
scanf("%d", &n);
for(i=0; i

It will put OFF all bits that are ON in the number n
It will test whether the individual bits of n are ON or OFF
It will put ON all bits that are OFF in the number n
It will report compilation errors in the if statement.

Discuss Question

Answer: Option B. -> It will test whether the individual bits of n are ON or OFF

Question 17.

Which of the following statements are correct about the program?

#include<stdio.h>
char *fun(unsigned int num, int base);
int main()
{
char *s;
s=fun(128, 2);
s=fun(128, 16);
printf("%s\n",s);
return 0;
}
char *fun(unsigned int num, int base)
{
static char buff[33];
char *ptr = &buff[sizeof(buff)-1];
*ptr = '\0';
do
{
*--ptr = "0123456789abcdef"[num %base];
num /=base;
}while(num!=0);
return ptr;
}

It converts a number to a given base.
It converts a number to its equivalent binary.
It converts a number to its equivalent hexadecimal.
It converts a number to its equivalent octal.

Discuss Question

Answer: Option A. -> It converts a number to a given base.

Question 18.

Which of the following statements are correct about the program?

#include<stdio.h>
int main()
{
unsigned int num;
int c=0;
scanf("%u", &num);
for(;num;num>>=1)
{
if(num & 1)
c++;
}
printf("%d", c);
return 0;
}

It counts the number of bits that are ON (1) in the number num.
It counts the number of bits that are OFF (0) in the number num.
It sets all bits in the number num to 1
Error

Discuss Question

Answer: Option A. -> It counts the number of bits that are ON (1) in the number num.

If we give input 4, it will print 1.
Binary-4 == 00000000 00000100 ; Total number of bits = 1.
If we give input 3, it will print 2.
Binary-3 == 00000000 00000011 ; Total number of bits = 2.
If we give input 511, it will print 9.
Binary-511 == 00000001 11111111 ; Total number of bits = 9.

Question 19.

What will be the output of the program?

#include<stdio.h>
int main()
{
printf("%d %dn", 32<<1, 32<<0);
printf("%d %dn", 32<<-1, 32<<-0);
printf("%d %dn", 32>>1, 32>>0);
printf("%d %dn", 32>>-1, 32>>-0);
return 0;
}
A. Garbage values
B. 64 32
0 32
16 32
0 32
C. All zeros
D. 8 0
0 0
32 0
0 16

It prints all even bits from num
It prints all odd bits from num
It prints binary equivalent num
Error

Discuss Question

Answer: Option C. -> It prints binary equivalent num

Answer: Option (B)

Question 20.

Which of the following statements are correct about the program?

#include<stdio.h>
int main()
{
unsigned int num;
int i;
scanf("%u", &num);
for(i=0; i

It prints all even bits from num
It prints all odd bits from num
It prints binary equivalent num
Error

Discuss Question

Answer: Option C. -> It prints binary equivalent num

If we give input 4, it will print 00000000 00000100 ;
If we give input 3, it will print 00000000 00000011 ;
If we give input 511, it will print 00000001 11111111 ;