Pointer to Pointer Dynamic Allocation
A pointer to pointer, denoted as double pointer (**).
This is a pointer that holds the memory address of another pointer. In simple words, it is a variable whose value is the address of another pointer. This concept might sound complex at first, but it provides a powerful mechanism for dealing with advanced dynamic memory allocation.
Syntax
main.cpp
12345678910111213#include <iostream> int main() { int x = 10; int *ptr1 = &x; int **ptr2 = &ptr1; // Accessing values using double pointer std::cout << "Address stored in ptr2 (address of ptr1): " << ptr2 << std::endl; std::cout << "Address stored in ptr1 (address of x): " << *ptr2 << std::endl; std::cout << "Value of x: " << **ptr2 << std::endl; }
- ptr1: is a pointer to an integer (
int*); - ptr2: is a double pointer to an integer (
int**).
Dynamic Allocation of a Two-Dimensional Array
If you want to create a two-dimensional array dynamically (at runtime) you have to use a pointer to a pointer for the rows.
And then initialize each row with dynamic array (like in previous chapter)
Swipe to start coding
Imagine you are working with a spreadsheet application where you need to create a table of numbers dynamically.
In this task, you will work with dynamic two-dimensional arrays and practice both allocation and deallocation of memory.
- Inside the function
createAndPrint2DArray, dynamically allocate a 2D array of integers with the given number of rows and columns. - Fill the array with values calculated as
row * columns + column, so each element is unique and depends on its position. - Print the array to the console in a tabular format.
- Properly release all dynamically allocated memory using
delete[]for each row and then for the array of pointers itself.
Solution
Thanks for your feedback!
single
Ask AI
Ask AI
Ask anything or try one of the suggested questions to begin our chat
Awesome!
Completion rate improved to 5.88Pointer to Pointer Dynamic Allocation
Swipe to show menu
A pointer to pointer, denoted as double pointer (**).
This is a pointer that holds the memory address of another pointer. In simple words, it is a variable whose value is the address of another pointer. This concept might sound complex at first, but it provides a powerful mechanism for dealing with advanced dynamic memory allocation.
Syntax
main.cpp
12345678910111213#include <iostream> int main() { int x = 10; int *ptr1 = &x; int **ptr2 = &ptr1; // Accessing values using double pointer std::cout << "Address stored in ptr2 (address of ptr1): " << ptr2 << std::endl; std::cout << "Address stored in ptr1 (address of x): " << *ptr2 << std::endl; std::cout << "Value of x: " << **ptr2 << std::endl; }
- ptr1: is a pointer to an integer (
int*); - ptr2: is a double pointer to an integer (
int**).
Dynamic Allocation of a Two-Dimensional Array
If you want to create a two-dimensional array dynamically (at runtime) you have to use a pointer to a pointer for the rows.
And then initialize each row with dynamic array (like in previous chapter)
Swipe to start coding
Imagine you are working with a spreadsheet application where you need to create a table of numbers dynamically.
In this task, you will work with dynamic two-dimensional arrays and practice both allocation and deallocation of memory.
- Inside the function
createAndPrint2DArray, dynamically allocate a 2D array of integers with the given number of rows and columns. - Fill the array with values calculated as
row * columns + column, so each element is unique and depends on its position. - Print the array to the console in a tabular format.
- Properly release all dynamically allocated memory using
delete[]for each row and then for the array of pointers itself.
Solution
Switch to desktop for real-world practiceContinue from where you are using one of the options belowThanks for your feedback!
single
