UMBC CMSC201, Computer Science I, Fall 1994 Sections 0101, 0102 and Honors

Rules for Variable Names

Classifying Characters

• a b c ... z are lower case letters.
• A B C ... Z are upper case letters.
• 0 1 2 ... 9 are the digits.
• Spaces, tabs and newlines are called white space.

Variable names ...

• can contain letters, digits and underscore _.
• cannot contain whitespace.
• must begin with a letter or _
• are case sensitive (upper and lower cases are different).
• cannot be a keyword.

The keywords are

   auto     double   int      struct
   break    else     long     switch
   case     enum     register typedef
   char     extern   return   union
   const    float    short    unsigned
   continue for      signed   void
   default  goto     sizeof   volatile
   do       if       static   while