Questions and answers for exam Preparation

MCQs

Total Questions : 15 | Page 1 of 2 pages

Question 1.

Are the expressions arr and &arr same for an array of 10 integers?

Discuss Question

Answer: Option B. -> No

Both mean two different things. arr gives the address of the first int, whereas the &arr gives

the address of array of ints.

Question 2.

Is there any difference int the following declarations?
int fun(int arr[]);
int fun(int arr[2]);

Discuss Question

Answer: Option B. -> No

No, both the statements are same. It is the prototype for the function fun() that accepts

one integer array as an parameter and returns an integer value.

Question 3.

Does this mentioning array name gives the base address in all the contexts?

Discuss Question

Answer: Option B. -> No

No, Mentioning the array name in C or C++ gives the base address in all contexts except one.

Syntactically, the compiler treats the array name as a pointer to the first element. You can

reference elements using array syntax, a[n], or using pointer syntax, *(a+n), and you can

even mix the usages within an expression.

When you pass an array name as a function argument, you are passing the "value of the

pointer", which means that you are implicitly passing the array by reference, even though

all parameters in functions are "call by value".

Question 4.

A pointer to a block of memory is effectively same as an array

True
False

Discuss Question

Answer: Option A. -> True

Yes, It is possible to allocate a block of memory (of arbitrary size) at run-time, using

the standard library's malloc function, and treat it as an array.

Question 5.

Which of the following statements are correct about an array?

1:The array int num[26]; can store 26 elements.

2:The expression num[1] designates the very first element in the array.

3:It is necessary to initialize the array at the time of declaration.

4:The declaration num[SIZE] is allowed if SIZE is a macro.

Discuss Question

Answer: Option B. -> 1,4

1. The array int num[26]; can store 26 elements. This statement is true.

2. The expression num[1] designates the very first element in the array. This statement is

false, because it designates the second element of the array.

3. It is necessary to initialize the array at the time of declaration. This statement is false.

4. The declaration num[SIZE] is allowed if SIZE is a macro. This statement is true, because

the MACRO just replaces the symbol SIZE with given value.

Hence the statements '1' and '4' are correct statements.

Question 6.

Which of the following statements are correct about 6 used in the program?
int num[6];
num[6]=21;

In the first statement 6 specifies a particular element, whereas in the second statement it specifies a type.
In the first statement 6 specifies a particular element, whereas in the second statement it specifies a type.
In the first statement 6 specifies a particular element, whereas in the second statement it specifies a array size.
In both the statement 6 specifies array size.

Discuss Question

Answer: Option B. -> In the first statement 6 specifies a particular element, whereas in the second statement it specifies a type.

The statement 'B' is correct, because int num[6]; specifies the size of array and num[6]=21;

designates the particular element(7^th element) of the array.

Question 7.

Which of the following statements are correct about the program below?

#include<stdio.h>
int main()
{
int size, i;
scanf("%d", &size);
int arr[size];
for(i=1; i

The code is erroneous since the subscript for array used in for loop is in the range 1 to size.
The code is erroneous since the values of array are getting scanned through the loop.
The code is erroneous since the statement declaring array is invalid.
The code is correct and runs successfully.

Discuss Question

Answer: Option C. -> The code is erroneous since the statement declaring array is invalid.

The statement int arr[size]; produces an error, because we cannot initialize the

size of array dynamically. Constant expression is required here.

Example: int arr[10];

One more point is there, that is, usually declaration is not allowed after calling

any function in a current block of code. In the given program the declaration

int arr[10]; is placed after a function call scanf().

Question 8.

Which of the following is correct way to define the function fun() in the below program?

#include<stdio.h>
int main()
{
int a[3][4];
fun(a);
return 0;
}
A.
void fun(int p[][4])
{
}
B.
void fun(int *p[4])
{
}
C.
void fun(int *p[][4])
{
}
D.
void fun(int *p[3][4])
{
}

A
A, B
B
B, D

Discuss Question

Answer: Option B. -> A, B

Answer: (A)

void fun(int p[][4]){ } is the correct way to write the function fun(). while the others are considered only the function fun() is called by using call by reference.

Question 9.

What will be the output of the program if the array begins 1200 in memory?

#include<stdio.h>
int main()
{
int arr[]={2, 3, 4, 1, 6};
printf("%u, %u, %u\n", arr, &arr[0], &arr);
return 0;
}

1200, 1202, 1204
1200, 1200, 1200
1200, 1204, 1208
1200, 1202, 1200

Discuss Question

Answer: Option B. -> 1200, 1200, 1200

Step 1: int arr[]={2, 3, 4, 1, 6}; The variable arr is declared as an integer array and initialized.

Step 2: printf("%u, %u, %un", arr, &arr[0], &arr); Here,

The base address of the array is 1200.

=> arr, &arr is pointing to the base address of the array arr.

=> &arr[0] is pointing to the address of the first element array arr. (ie. base address)

Hence the output of the program is 1200, 1200, 1200

Question 10.

Which of the following statements mentioning the name of the array begins DOES NOT yield

the base address?

1: When array name is used with the sizeof operator.
2: When array name is operand of the & operator.
3: When array name is passed to scanf() function.
4: When array name is passed to printf() function.