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; } |
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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; } |
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