Reference Variables in C++

Reference Variables

A reference variable is a name that acts as an alternative name for a previously defined variable.  A reference variable is created as follows:

                        Data-type & reference-name = variable-name

Example:

                 float total = 100;

                 float & sum = total;

total is a float type variable that has already been declared; sum is the alternative name declared to represent the variable total.  Both the variables refer to the same data object in memory.  Now, the statements

                 cout << total;

and

                 cout<< sum;

Both variables will print the same value and if we change values, it will reflect in both the variables.

 A reference variable must be initialized the time of declaration. C++ also assigns additional meaning to the symbol &. Here, & is not an address operator.  The notation float & means reference to float.  Other examples are

   int n[10];

   int & x = n[10];   // x is alias for n[10]

   char & a =’\n’;    // initialize reference to a literal.

The variable x is an alternative to the array element n[10].  The variable a is initialized to the new-line constant.