Practice exercise -- Tokens: basic elements of C++


Special symbols: 

    mathematical:  +    -     *    / 
    punctuation:   .    ;     ?    , 
    logical:       <=   ==   !=   >=      (two-character symbols)
    other:         ( )  { }  [ ]  blank   ...


Word symbols: reserved words or keywords, always lowercase

    int, double, float, char, const, void, return ...


Identifiers:  names of things that appear in a program; 
    they consist of letters, digits, and  the underscore character (_).  
    They should not start with a digit, and are case-sensitive.  
    Two predefined identifiers are cin and cout.


Indicate whether the following would be classified as a special symbol, word 
    symbol, identifier, or is invalid:

Token         Special symbol       Word Symbol      Identifier      Invalid
--------      --------------       -----------      ----------      -------
*

int

lastName

$amount

r2d2

double

cin

3D

PI

!=

one Way

Void

LAB_FEE

SQL+