Pointers in C++

Pointers in C++ are special variables that store the address or memory location of another variable.

Syntax

datatype *variable_name;   
int *x; // x can point to an address which holds int data  

How to use Pointers?

To use pointers in C++, follow the steps below:

  1. Create a pointer variable.
  2. Assigning the address of another variable to a pointer using the unary operator (&).
  3. Accessing the value at the address using unary operator (*).
Example

#include <iostream>
using namespace std;

int main()
{
    int var = 18;
    int *ptr;
    ptr = &var;
    
    cout << "Initial value of var is: " << var << endl;
    cout << "Initial value of *ptr is: " << *ptr << endl << endl;
    
    // changing the value of var using ptr
    *ptr = 47;
    
    cout << "New value of *ptr is: " << *ptr << endl;
    cout << "New value of var is: " << var << endl;
    
    return 0;
}
Output
Initial value of var is: 18
Initial value of *ptr is: 18

New value of *ptr is: 47
New value of var is: 47

Advantage of using Pointers in C++

  • Pointers make us able to access any memory location in the computer's memory.
  • Pointers improve speed performance.
  • Pointers efficiently handle arrays and strings.
  • Functions can return multiple values using Pointers.
  • Pointers can reduce code and save memory.

Symbols used in pointer

Symbol Name Description
& (Ampersand) Address operator Used to determine the address of a variable.
* (Asterisk) Indirection operator Used to access the value of an address.