Mastering C++ Pointers

What is a pointer in C++?

• A pointer is a special kind of loop in C++.

• A pointer is a variable that stores a string in C++.

• A pointer is a type of function in C++.

• A pointer is a variable that holds the address of another variable in C++.

How do you declare a pointer variable?

• int *ptr;

• ptr: int;

• pointer int ptr;

• int ptr;

What is pointer arithmetic?

• Pointer arithmetic is the process of converting pointers to integers.

• Pointer arithmetic is the process of performing arithmetic operations on pointers to navigate through memory addresses.

• Pointer arithmetic is the method of allocating memory for variables.

• Pointer arithmetic refers to the use of pointers in function calls.

What is the purpose of dynamic memory allocation?

• To create fixed-size arrays that cannot be resized.

• The purpose of dynamic memory allocation is to allocate memory at runtime, allowing for flexible and efficient memory management.

• To reduce the overall memory usage of a program.

• To allocate memory only at compile time.

How do you allocate memory dynamically in C++?

• Use 'calloc' for allocation and 'realloc' for deallocation.

• Allocate memory using 'alloca' and 'dealloca'.

• Use 'new' for allocation and 'delete' for deallocation.

• Use 'malloc' for allocation and 'free' for deallocation.

How do you check if a pointer is null?

• Check 'if (ptr != NULL)'

• Use 'if (ptr = NULL)'

• Use 'if (ptr == NULL)' or 'if (ptr == nullptr)'.

• Use 'if (ptr != 0)'

How do you deallocate memory in C++?

• Use 'dispose' for both single objects and arrays.

• Use 'free' to deallocate memory in C++.

• Use 'malloc' to allocate memory only.

• Use 'delete' for single objects and 'delete[]' for arrays.

What happens if you forget to deallocate memory?

• Memory will be allocated indefinitely without any issues.

• Memory leaks occur, potentially leading to performance issues or crashes.

• The system will crash immediately after forgetting to deallocate.

• The program will automatically free up the memory later.

How are pointers and arrays related in C++?

• Pointers and arrays are related in C++ as the name of an array acts as a pointer to its first element, allowing pointer arithmetic to access array elements.

• Pointers can only be used with dynamic memory allocation.

• Arrays can be resized dynamically in C++ unlike pointers.

• Pointers and arrays are completely unrelated in C++.

How do you access array elements using pointers?

• Array elements can only be accessed using their index without pointers.

• You can access array elements by using the array name directly.

• Pointers cannot be used to access array elements in C.

• You can access array elements using pointers by declaring a pointer to the array and dereferencing it with the appropriate index.