C++ Programming Code Examples
C++ > Pointers Code Examples
Pointer Simple with Reference operator (&) and Dereference operator (*)
/* Pointer Simple with Reference operator (&) and Dereference operator (*)
The pointer is a programming language data type whose value refers directly to (or "points to") another value stored elsewhere in the computer memory using its address.
Reference operator ("&")
The reference operator noted by ampersand ("&"), is also a unary operator in c languages that uses for assign address of the variables. It returns the pointer address of the variable. This is called "referencing" operater.
Dereference operator ("*")
The dereference operator or indirection operator, noted by asterisk ("*"), is also a unary operator in c languages that uses for pointer variables. It operates on a pointer variable, and returns l-value equivalent to the value at the pointer address. This is called "dereferencing" the pointer. */
// Header Files
#include <iostream>
#include<conio.h>
using namespace std;
int main() {
//Pointer Variable Declaration for Integer Data Type
int* pt;
int var;
cout << "C++ Pointer Example for Reference operator (&) and Dereference operator (*)\n";
var = 1;
cout << "Address of var :" << &var << "\n";
cout << "Value of var :" << var << "\n\n";
//& takes the address of var , Here now pt == &var, so *pt == var
pt = &var;
cout << "Address of Pointer pt :" << pt << "\n";
cout << "Content of Pointer pt :" << *pt << "\n\n";
var = 2;
cout << "Address of Pointer pt :" << pt << "\n";
cout << "Content of Pointer pt :" << *pt << "\n\n";
//Assign Values using dereference operator
*pt = 3;
cout << "Address of var :" << &var << "\n";
cout << "Value of var :" << var << "\n\n";
getch();
return 0;
}
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