1 $Which operator is used to return the memory address of a variable?$

A.

*

B.

&

C.

->

D.

%

2 $What is the correct syntax to declare a pointer to an integer?$

A.

int ptr;

B.

int *ptr;

C.

int &ptr;

D.

ptr int;

3 $What is the size of a pointer variable in a 64-bit architecture?$

A.

2 bytes

B.

4 bytes

C.

8 bytes

D.

Depends on the data type it points to

4 $What is the result of the expression *ptr if ptr is a pointer holding the address of variable x ?$

A.

The address of x

B.

The value of x

C.

The address of ptr

D.

The size of x

5 $What is a Null Pointer ?$

A.

A pointer that points to a specific valid address.

B.

A pointer that has not been initialized.

C.

A pointer pointing to address 0 or explicitly assigned NULL.

D.

A pointer pointing to a deleted variable.

6 $Which of the following defines a Void Pointer ?$

A.

A pointer that points to nothing.

B.

A generic pointer that can point to any data type.

C.

A pointer that returns a null value.

D.

A pointer used for arithmetic operations.

7 $What happens if you try to dereference a void pointer without typecasting?$

A.

It returns 0.

B.

It works normally.

C.

It causes a compilation error.

D.

It returns garbage value.

8 $A pointer that points to a memory location that has been deleted (freed) is called:$

A.

Null Pointer

B.

Void Pointer

C.

Dangling Pointer

D.

Wild Pointer

9 $What is a Wild Pointer ?$

A.

A pointer pointing to NULL.

B.

An uninitialized pointer.

C.

A pointer pointing to a function.

D.

A pointer stored in heap memory.

10 $If int *p points to address 1000 and sizeof(int) is 4 bytes, what is the value of p + 1 ?$

A.

1001

B.

1004

C.

1002

D.

1010

11 $Which of the following arithmetic operations is NOT allowed on pointers?$

A.

Adding an integer to a pointer

B.

Subtracting an integer from a pointer

C.

Subtracting two pointers of the same type

D.

Adding two pointers

12 $What is the result of subtracting two pointers of the same type?$

A.

The sum of their addresses

B.

The number of elements between the two pointers

C.

The multiplication of addresses

D.

A pointer to the middle element

13 $Consider the declaration int a[5] = {10, 20, 30, 40, 50}; . What is *(a + 2) equal to?$

A.

10

B.

20

C.

30

D.

Address of 30

14 $Which of the following is equivalent to arr[i] ?$

A.

&arr + i

B.

*(arr + i)

C.

*arr + i

D.

(arr + i)

15 $What is the primary difference between an array name and a pointer variable?$

A.

Array name is a constant pointer; pointer variable is not.

B.

Pointer variable cannot store address of array.

C.

Array name cannot be dereferenced.

D.

There is no difference.

16 $When passing a pointer to a function, what method of parameter passing is simulated?$

A.

Call by value

B.

Call by reference

C.

Call by name

D.

Call by constant

17 $Which library header must be included to use malloc, calloc, and free ?$

A.

<stdio.h>

B.

<string.h>

C.

<stdlib.h>

D.

<alloc.h>

18 $What is the return type of the malloc function?$

A.

int *

B.

char *

C.

void *

D.

null

19 $How does calloc differ from malloc regarding memory initialization?$

A.

malloc initializes memory to zero; calloc does not.

B.

calloc initializes memory to zero; malloc contains garbage values.

C.

Both initialize memory to zero.

D.

Neither initializes memory.

20 $Which function is used to resize a previously allocated memory block?$

A.

malloc

B.

calloc

C.

realloc

D.

memalloc

21 $What is the syntax for calloc ?$

A.

ptr = calloc(byte_size);

B.

ptr = calloc(num_elements, element_size);

C.

ptr = calloc(element_size, num_elements);

D.

ptr = calloc(num_elements);

22 $What happens if you do not free dynamically allocated memory before the program terminates?$

A.

Compilation error

B.

Memory Leak

C.

Segmentation fault

D.

Nothing, OS always frees it instantly

23 $What value do malloc and calloc return if the memory allocation fails?$

A.

-1

B.

0

C.

NULL

D.

Garbage value

24 $In C, strings are represented as:$

A.

A primitive data type 'string'

B.

An array of characters terminated by a null character

C.

An object of String class

D.

A pointer to an integer

25 $Which character serves as the string terminator in C?$

A.

'\n'

B.

'\0'

C.

'0'

D.

'\t'

26 $What is the output size of sizeof("Hello") ?$

A.

5

B.

6

C.

4

D.

8

27 $Which function is unsafe to use for reading strings because it does not check buffer length?$

A.

scanf

B.

fgets

C.

gets

D.

getchar

28 $What is the difference between char s[] = "Hello"; and char *p = "Hello"; ?$

A.

No difference.

B.

s is modifiable, p points to a string literal which is likely read-only.

C.

p is modifiable, s is read-only.

D.

s allows pointer arithmetic, p does not.

29 $Which format specifier is used to read a string using scanf ?$

A.

%c

B.

%s

C.

%d

D.

%f

30 $Which library function calculates the length of a string?$

A.

strlength()

B.

size()

C.

strlen()

D.

strcount()

31 $What does strcpy(dest, src) do?$

A.

Concatenates src to dest

B.

Compares dest and src

C.

Copies the content of src to dest

D.

Returns the length of src

32 $Which header file is required for string manipulation functions like strcpy and strcmp ?$

A.

<stdlib.h>

B.

<string.h>

C.

<stdio.h>

D.

<conio.h>

33 $What does strcmp(s1, s2) return if s1 and s2 are identical?$

A.

1

B.

-1

C.

0

D.

Non-zero

34 $If strcat(s1, s2) is executed, what is the result?$

A.

s1 is appended to s2

B.

s2 is appended to s1

C.

s1 and s2 are copied to a new string

D.

s1 is overwritten by s2

35 $What will strlen("Code") return?$

A.

4

B.

5

C.

3

D.

Undefined

36 $How do you correctly convert a character digit'5' to the integer 5 ?$

A.

'5' + 0

B.

(int)'5'

C.

'5' - '0'

D.

atoi('5')

37 $What function is used to convert a string to a long integer?$

A.

atoi

B.

atol

C.

itoa

D.

strtod

38 $What logic converts an uppercase letter ch to lowercase?$

A.

ch - 32

B.

ch + 32

C.

ch * 2

D.

ch / 2

39 $Which function searches for the first occurrence of a character in a string?$

A.

strchr()

B.

strstr()

C.

strrchr()

D.

strtok()

40 $What does strstr(haystack, needle) do?$

A.

Finds a character in a string

B.

Concatenates two strings

C.

Finds the first occurrence of substring 'needle' in 'haystack'

D.

Compares two strings

41 $What is the difference between printf("%s", str) and puts(str) ?$

A.

No difference.

B.

printf adds a newline automatically, puts does not.

C.

puts adds a newline automatically, printf does not.

D.

puts can format output, printf cannot.

42 $Consider char *str = "Hello"; . What is valid?$

A.

str[0] = 'h';

B.

str = "World";

C.

*str = 'M';

D.

None of the above

43 $What is the purpose of void * in malloc ?$

A.

To allocate memory for void types only

B.

To act as a generic pointer type that can be cast to any type

C.

To indicate the function returns nothing

D.

To create a null pointer

44 $What is the priority of *ptr++ ?$

A.

Increment ptr, then dereference

B.

Dereference ptr, then increment the value pointed to

C.

Dereference ptr, then increment the pointer

D.

Undefined

45 $Which of the following creates a pointer to a pointer (Double Pointer)?$

A.

int **p;

B.

int &p;

C.

int p;

D.

int p**;

46 $Why is free() necessary in dynamic memory allocation?$

A.

To initialize the memory

B.

To return memory to the heap for reuse

C.

To clear the contents of the variables

D.

To delete the pointer variable

47 $How do you read a string with spaces using scanf ?$

A.

scanf("%s", str);

B.

scanf("%[^]s", str);

C.

scanf("%s space", str);

D.

scanf("% line", str);

48 $If int arr[] = {1, 2, 3}; and int *p = arr;, what is p[1] ?$

A.

1

B.

2

C.

3

D.

Address of 2

49 $Which operator accesses a member of a structure using a pointer to that structure?$

A.

.

B.

->

C.

*

D.

&

50 $What is the output of printf("%d", *&a) if a = 10 ?$

A.

Address of a

B.

10

C.

Garbage

D.

Error

Unit 5 - Practice Quiz