Reference Operator:  &

decl-specifiers & cv-qualifier-list_opt dname ;

A reference is a 16-bit or 32-bit quantity that holds the address of an object but behaves syntactically like that object. A reference declaration consists of an (optional) list of specifiers followed by a reference declarator.

In C++, any object whose address can be converted to a given pointer type can also be converted to the analogous reference type. For example, any object whose address can be converted to type char * can also be converted to type char &. No constructors or class conversion functions are called to make a conversion to a reference type.

Example

In the following example, the variable x is passed by reference and modified by the AddIt function.

// Example of the reference operator
void AddIt(int& x)
{
      x += 2;
}

int x;

x = 3;
AddIt(x);
printf("%d, x) ;   // the value of x is now 5