C++ Pointer (& and *) Operators
C++ provides two pointer operators which are (a) Address of Operator & and (b) Indirection Operator *.
A pointer is a variable that contains the address of another variable or you can say that a variable that contains the address of another variable is said to "point to" the other variable. A variable can be any data type including an object, structure or again pointer itself.
The . (dot) operator and the -> (arrow) operator are used to reference individual members of classes, structures, and unions.
The Address of Operator &:
The & is a unary operator that returns the memory address of its operand. For example, if var is an integer variable, then &var is its address. This operator has the same precedence and right-to-left associativity as the other unary operators.
You should read the & operator as "the address of" which means &var will be read as "the address of var".
The Indirection Operator *:
The second operator is indirection Operator *, and it is the complement of &. It is a unary operator that returns the value of the variable located at the address specified by its operand.
The following program executes the two operations
#include <iostream>
using namespace std;
int main ()
{
int var;
int *ptr;
int val;
var = 3000;
// take the address of var
ptr = &var;
// take the value available at ptr
val = *ptr;
cout << "Value of var :" << var << endl;
cout << "Value of ptr :" << ptr << endl;
cout << "Value of val :" << val << endl;
return 0;
}
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When the above code is compiled and executed, it produces following result:
Value of var :3000
Value of ptr :0xbff64494
Value of val :3000
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