Difference between int (*p)[3] and int* p[3]?

Pointers store the address of variables or a memory location. Pointers are a symbolic representation of addresses. They enable programs to simulate call-by-reference as well as to create and manipulate dynamic data structures. Its general declaration in C/C++ has the format:

Syntax:

datatype *var_name; 

Example:

int *ptr;

In this example “ptr” is a variable name of the pointer that holds address of an integer variable.

In this article, the focus is to differentiate between the two declarations of pointers i.e., int (*p)[3] and int *p[3].

For int (*p)[3]: Here “p” is the variable name of the pointer which can point to an array of three integers.

Below is an example to illustrate the use of int (*p)[3]:

C++

// C++ program to illustrate the use
// of int (*p)[3]
#include <iostream>
using namespace std;

// Driver Code
int main()
{
    // Declaring a pointer to store address
    // pointing to an array of size 3
    int(*p)[3];

    // Define an array of size 3
    int a[3] = { 1, 2, 3 };

    // Store the base address of the
    // array in the pointer variable
    p = &a;

    // Print the results
    for (int i = 0; i < 3; i++) {
        cout << *(*(p) + i) << " ";
    }

    return 0;
}

Output:

1 2 3

For int *p[3]: Here “p” is an array of the size 3 which can store integer pointers.

Below is an example to illustrate the use of int *p[3]:

C++

// C++ program to illustrate the use
// of int*p[3]
#include <bits/stdc++.h>
using namespace std;

// Driver Code
int main()
{
    // Declare an array of size 3 which
    // will store integer pointers
    int* p[3];

    // Integer variables
    int a = 1, b = 2, c = 3;

    // Store the address of integer
    // variable at each index
    p[0] = &a;
    p[1] = &b;
    p[2] = &c;

    // Print the result
    for (int i = 0; i < 3; i++) {
        cout << *p[i] << " ";
    }

    return 0;
}

Output:

1 2 3