POINTERS

The reason for using pointers in a C program is

• Pointers allow different functions to share and modify their local variables.

• To pass large structures so that complete copy of the structure can be avoided.

• Pointers enable complex “linked" data structures like linked lists and binary trees

• 
  All of the above

What is the primary advantage of using dynamic memory allocation in C?

• It prevents memory leaks.

• 
  All of the above

• It allows for the allocation of memory at runtime.

• It simplifies the code structure.

Which of the following correctly describes a null pointer in C?

• A pointer that points to the first element of an array.

• A pointer that is not assigned any value.

• A pointer that points to a valid memory location.

• 
  None of the above

In C, what is the result of dereferencing a pointer that has not been initialized?

• 
  All of the above

• It will return a random value.

• It will cause a segmentation fault.

• It will return zero.

What happens if you try to free a pointer that has already been freed in C?

• 
  All of the above

• It may cause undefined behavior.

• It will have no effect.

• It will cause a memory leak.

Which of the following is a valid way to declare a pointer to an integer in C?

• int *ptr;

• 
  All of the above

• ptr int;

• int ptr;

What is the purpose of the 'sizeof' operator in C?

• To determine the size of a variable in bytes.

• To allocate memory dynamically.

• 
  None of the above

• To compare two variables.

# include <stdio.h>

void fun(int x)

{

x = 30;

}

int main()

{

int y = 20;

fun(y);

printf("%d", y);

return 0;

}

• 30

• 20

• Compiler Error

• Runtime Error

What will be the output of the following code snippet?

int a = 5; int *p = &a; *p = 10; printf("%d", a);

• 10

• 5

• Compiler Error

• Runtime Error

Which of the following statements about pointers is true?

• Pointers can be incremented to point to the next memory location.

• Pointers cannot be used with arrays.

• Pointers can only point to variables of the same type.

• 
  None of the above