Pointer Arrays and Pointers to Pointers in C++

Pointer Arrays and Pointers to Pointers are key concepts in C++ programming.

Pointer Array Definition

A pointer array is an array where each element is of pointer type. This means that every element of the pointer array can hold an address. The declaration format is:

int *p[4];  // Array of 4 pointers, each pointing to an int.

Here, p is an array name with 4 elements, and each element can store the address of an int variable.

Pointer to an Array

You can also define a pointer that points to an array:

int (*p)[4];  // Pointer to a 1D array of 4 integers.

In this case, p points to an entire array with four int-type elements.

Key Differences:

- int *p[4];: This is an array of 4 pointers, each pointing to an integer.

- int (*p)[4];: This is a pointer to an array of 4 integers.

Accessing Array Elements via Pointers:

For an array p of pointers:

p[0], p[1], p[2], p[3]  // These hold addresses of int variables.

For a pointer to an array:

*p  // Points to the first element of the array it refers to.

Example Usage

If we need to manipulate multiple arrays or dynamically allocate memory for arrays, pointer arrays and pointers to pointers become essential tools in C++.