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
#include <iostream> int main() { int x = 10; int *ptr1 = &x; int **ptr2 = &ptr1; // Accessing values using double pointer std::cout << "Location of ptr2: " << ptr2 << std::endl; std::cout << "Location of ptr1: " << *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)
Opgave
Swipe to start coding
- Dynamically allocate a two dimensional array.
- Dynamically allocate the arrays as elements.
- Free all allocated memory.
Løsning
solution
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