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Examples of some valid variable names are:

                              Valid Variable Name                             Reason

                          Gaurav123                       Starts with a letter
                          _usha93                         Starts with an underscore symbol

                 Examples of some invalid variables are:

                             Invalid Variable Name                             Reason

                          1_Name                          Cannot start with a digit
                          @Address                        Cannot starts with a special symbol (except _ )

                          int                             Keyword cannot be used as variable name
                          User Name                       Spaces are not allowed in variable names

                 Declaring a Variable

                 C++ is a strongly-typed language, which means you need to declare a variable before using it.
                 You also need to specify the data type of the variable, so that the compiler understands how the
                 variable is interpreted. When a variable is declared, the computer reserves memory space for it.
                 Syntax to declare a variable in C++ is as follows:

                 data_type variable_name;
                 Where,  data_type  specifies  the  type  of  value  a  variable  can  store  (e.g.,  int,  float,  char)  and
                 variable_name is the name of the variable which is used to access the variable in the program.

                 For example:
                       int age;

                       char grade;
                 Where, int and char are the data types, and, age and grade are the variable names. You can also
                 declare multiple variables of the same type in a single line in the following way:
                       int emp_code, age, pincode;
                 Initialising a Variable


                 Initialising a variable means to assign a value to the variable. You can assign a value to a variable
                 using the assignment operator (‘=’) in the following way:
                      age = 21;               // initialising an integer variable

                      grade = 'A';            // Initialising a character variable
                 In the above example, you can see that the single quotes (' ') are used to initialise a character
                 variable. A variable can also be initialised during their declaration itself in the following way:

                       int age = 21;
                       char grade = 'A';
                 Let's write a program to show this concept more clearly.




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                                                                                         Getting Started with C++
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