#3 Tokens of C

➤Delimiters :-

 Delimiters are used for syntactic purpose in C.

Delimiters are:-

• :    colon                     used for label
• ;    semicolon              end of statement
• ()   parentheses           used in expressions
• []   square brackets     used for arrays    
• {}  curly braces           used for block of statements
• #    hash                       preprocessor directive
• ,     comma                   variable delimiter

➤Identifiers :-

• Identifiers are user defined words .
• They are used to give names to entities like variables,arrays, functions, structures etc.

   ⏩Rules for naming identifiers are given below:-

1. The name should consist of only uppercase and lower case letters, digits and underscore sign(_).
2. First character should be an alphabet or underscore.
3. The name should not be a keyword.
4. Blank space is not permitted .
5. Since C is case sensitive, the uppercase and lowercase letters are considered different. For new, New and NEW are three different identifiers.

➤Expressions :-

•  An expressions is a combination of operators, constants, variables and functions calls. 
• An expressions can be arithmetic , logical or relational.

Some examples of expressions are:-

               x+y        - arithmetic operation

               a=b+c    - uses of two operator(=) and (+)

               a>b        - relational expression

               a==b      -logical expression

               func(a,b)-function call

➤Comments:-

• Comments are used for increasing readability of the program.
• They explain the purpose of the program.
• There can be single line or multiple line comments.
• The closing delimiter can't be used inside a comment.

comments are written as:-

                              /* statements to be comment */

                                             or

                              // statements to be comment