Class 12 Pointers in C++ Important Questions
Chapter 7 - Pointers in C++
This page contains important questions on Pointers in C++ for Class 12 Computer Science. The questions cover pointer declaration and initialization, dynamic memory allocation, new and delete operators, pointers and arrays, and pointers to structures, self-referential structures. These questions are useful for AHSEC/ASSEB Class 12 exam preparation
1. What is a pointer?
Answer :A pointer is a variable that stores the memory address of another variable.
2. Why do we need pointers?
Answer :Pointers are commonly used for:
- Accessing the address of a variable.
- Accessing a value indirectly.
- Working efficiently with arrays.
- Passing addresses to functions.
3. How do we declare a pointer?
Answer :A pointer is declared by placing an asterisk (*) before the pointer variable name.
Syntax for declaring a pointer variable is:
data_type *pointer_name
Examples
int *p;
float *q;
4. What is Address-of operator?
Answer :The & operator is called the address-of operator. It returns the memory address of a variable.
Syntax
&variable_name
Example
int x = 50;
cout << &x;
Here:
- x refers to the value stored in the variable
- &x gives the memory address of the variable
5. What is dereferencing?
Answer :Dereferencing a pointer means accessing the value stored at the memory address held by the pointer.
6. What is null pointer?
Answer : A pointer that does not point to any valid memory location is called null pointer.
7. What is dynamic memory allocation?
Answer :Sometimes a program needs to allocate memory while it is running. This is called dynamic memory allocation. C++ provides the new operator for allocating memory dynamically and delete operator to release dynamically allocated memory.
8.What is the use of new operator?
Answer : The new operator is used to allocate memory dynamically.
Syntax
pointer = new data_type;
Example
int *p = new int;
This statement creates memory for an integer and stores its address in p.
9. What is the use of delete operator?
Answer : Memory allocated using new should be released when it is no longer required.The delete operator is used to release dynamically allocated memory
10. What is an array of pointers?
Answer : An array of pointers is an array in which every element is a pointer
11. What is the use of arrow operator?
Answer :The arrow operator (->) is used to access the members of a structure or class through a pointer
12.What is self-referential structure?
Answer :
A self-referential structure is a structure that contains a pointer to another structure of the same type.This concept is particularly important in linked lists and other dynamic data structures.
13. Which operator is used to obtain the address of a variable?
Answer: The address-of operator &.
14. Which operator is used to access the value pointed to by a pointer?
Answer : The dereference operator *