Questions and answers for exam Preparation

MCQs

Total Questions : 66 | Page 5 of 7 pages

Question 41.

By default a real number is treated as a

float
double
long double
far double

Discuss Question

Answer: Option B. -> double

In computing, 'real number' often refers to non-complex floating-point numbers.It

include both rational numbers, such as 42 and 3/4, and irrational numbers such

as pi = 3.14159265...

When the accuracy of the floating point number is insufficient, we can use the doubleto

define the number. The double is same as float but with longer precision and takes double

space (8 bytes) than float.

To extend the precision further we can use long double which occupies 10 bytes of memory

space.

Question 42.

How would you round off a value from 1.66 to 2.0?

ceil(1.66)
floor(1.66)
roundup(1.66)
roundto(1.66)

Discuss Question

Answer: Option A. -> ceil(1.66)

#include<stdio.h>
#include<math.h>
int main()
{
printf("\n Result : %f" , ceil(1.44) );
printf("\n Result : %f" , ceil(1.66) );
printf("\n Result : %f" , floor(1.44) );
printf("\n Result : %f" , floor(1.66) );
return 0;
}
// Output:
// Result : 2.000000
// Result : 2.000000
// Result : 1.000000
// Result : 1.000000

Question 43.

Which of the following special symbol allowed in a variable name?

* (asterisk)
| (pipeline)
- (hyphen)
_ (underscore)

Discuss Question

Answer: Option D. -> _ (underscore)

Variable names in C are made up of letters (upper and lower case) and digits. The underscore character ("_") is also permitted. Names must not begin with a digit.

Examples of valid (but not very descriptive) C variable names:
=> foo
=> Bar
=> BAZ
=> foo_bar
=> _foo42
=> _

=> QuUx

Question 44.

What are the types of linkages?

Internal and External
External, Internal and None
External and None
Internal

Discuss Question

Answer: Option B. -> External, Internal and None

External Linkage-> means global, non-static variables and functions.

Internal Linkage-> means static variables and functions with file scope.

None Linkage-> means Local variables.

Question 45.

Is there any difference between following declarations?

1: extern int fun();

2: int fun();

Both are identical
No difference, except extern int fun(); is probably in another file
int fun(); is overrided with extern int fun();
None of these

Discuss Question

Answer: Option B. -> No difference, except extern int fun(); is probably in another file

extern int fun(); declaration in C is to indicate the existence of a global function

and it is defined externally to the current module or in another file.

int fun(); declaration in C is to indicate the existence of a function inside the

current module or in the same file.

Question 46.

Which of the following statements should be used to obtain a remainder after dividing 3.14 by 2.1 ?

rem = 3.14 % 2.1;
rem = modf(3.14, 2.1);
rem = modf(3.14, 2.1);
Remainder cannot be obtain in floating point division.

Discuss Question

Answer: Option C. -> rem = modf(3.14, 2.1);

fmod (x, y) - Calculates x modulo y, the remainder of x/y.
This function is the same as the modulus operator. But fmod() performs floating point
divisions.

#include <stdio.h>
#include <math.h>
int main ()
{
printf ("fmod of 3.14/2.1 is %lf\n", fmod (3.14,2.1) );
return 0;
}

Output:
fmod of 3.14/2.1 is 1.040000

Question 47.

Point out the error in the following program.

#include<stdio.h>
int main()
{
int (*p)() = fun;
(*p)();
return 0;
}
int fun()
{
printf("Placementadda");
return 0;
}

Error: in int(*p)() = fun;
Error: fun() prototype not defined
No error
None of these

Discuss Question

Answer: Option B. -> Error: fun() prototype not defined

The compiler will not know that the function int fun() exists. So we have to define the function prototype of int fun();
To overcome this error, see the below program

#include<stdio.h>
int fun(); /* function prototype */
int main()
{
int (*p)() = fun;
(*p)();
return 0;
}
int fun()
{
printf("placementadda");
return 0;
}

Question 48.
What will be output when you will execute following c code?
#include<stdio.h>
int main()
{
printf("%d\t", sizeof(6.5));
printf("%d\t", sizeof(90000));
printf("%d\t", sizeof('A'));
return 0;
}

4 2 1
8 2 1
4 4 1
8 4 1
8 4 2

Discuss Question

Answer: Option E. -> 8 4 2

By default data type of numeric constants is:

6.5 : double

90000: long int

â€˜Aâ€™: char

double is 8 byte

long int is 8 byte

Character constant is 2 byte

Question 49.

What would be the output of the program in 16 bit platform (Turbo C under DOS)?

#include<stdio.h>
int main()
{
extern int i;
i = 20;
printf("%d`setminus`n", sizeof(i));
return 0;
}

2
4
Would vary from compiler to compiler
Error, i undefined

Discuss Question

Answer: Option D. -> Error, i undefined

Linker Error : Undefined symbol 'i'
The statement extern int i
specifies to the compiler that the memory for 'i'
is allocated in some other program and that address will be given to the
current program at the time of linking. But linker finds that no other
variable of name 'i' is available in any other program with memory space allocated for it. Hence a linker error has occurred.

Question 50.

By default a real number is treated as a

float
double
long double
far double

Discuss Question

Answer: Option B. -> double

In computing, 'real number' often refers to non-complex floating-point
numbers. It include both rational numbers, such as 42 and 3/4, and
irrational numbers such as pi = 3.14159265...

When the accuracy of the floating point number is insufficient, we can use the double to define the number. The double is same as float but with longer precision and takes double space (8 bytes) than float.

To extend the precision further we can use long double which occupies 10 bytes of memory space.