Turbo Pascal Statements 
                         Case - Conditional Statement 

     The Case statement consists of an expression (The Selector), followed
     by a list of statements.  Each statement in the list is prefixed with
     at least one constant (Case Constant) or with the reserved word, Else.

     The Selector must be of byte- or word-sized ordinal type.  All Case
     Constants must be unique and of a ordinal type that is compatible with
     the Selector type.

     A statement is executed if it is prefixed by a Case Constant that is
     equal to the value of the Selector or a Case Range that contains the
     value of the Selector.  If no such constant or range exists, and an
     else part is present, the statement that following else is executed.
     If there is no else part present, no statements are executed.


 Case statement 

           +------------+       +------+
   Case --.| expression |-. of .| case |------------------------------.  End
           +------------+     . +------+ | |               | |     |
                              |          | |               | |     |
                              |          | | +-----------+ | |     |
                              +---- ; .--+ +.| else part |.+ +. ; .+
                                             +-----------+

 Case 
                        +----------------------+
                        |                      |
           +----------+ |         +----------+ .
       ---.| constant |---. .. --.| constant |-----.  :  statement
        .  +----------+           +----------+   |
        |                      (Case Range)      |
        |                                        |
        +------------  ,  -----------------------+
                 (Constant List)

 Else part 

                   +-----------+
     Else  ---.| statement |----.
                   +-----------+


  EXAMPLE:  Var
               OrdVal : Integer;

            Begin
               ReadLn(OrdVal);

               Case OrdVal of
                  1..3 : Begin
                            Write('OrdVal is 1 or');
                            WriteLn(' OrdVal is 3);
                         End;
                  5, 7 : WriteLn('OrdVal is 5 or 7');
                  10   : WriteLn('OrdVal is 10 ;
               Else
                  WriteLn('OrdVal is',OrdVal);
               End;  (* end case *)
            End.