Set Types  79  Examples of assignments  Set operations are intended to be relatively fast and can be used to  eliminate more complicated tests. A simpler test for:  is:  Produces as results (assuming appropriate input):  Huel  :=  [Red];  Hue2  :=  [];  Hue2  := Hue2  +  [succ(Red)];  Letters  ['A' ,'B' ,'C' ,'0' ,'E' ,'F' ,'G' ,'H' ,'I',  'J' ,'K' , 'L' ,'M' , 'N' , '0' , 'P' ,'Q' , 'R' ,  , S' , ' T' , 'U' , 'V' , 'W' , ' X' , ' Y' , ' Z' ] ;  Vowels:=  ['A','E','I','O',U];  Consonants  := Letters - Vowels;  Add  :=  [2,3]  <= Opcode  if  (Ch='A')or(Ch='E')or(Ch='I')or(Ch='O')or(Ch='U')  then S  if Ch  in  ['A','E','I','O','U']  then S  program Convert(Input,Output);  { Program 8.1 - Read a  sequence of digits and convert  them to the integer they represent.  Assume no leading sign.  }  var  Ch:  Char;  Digits:  set of '0' .. '9';  Number:  Integer;  begin  Digits  :=  ['0' .. '9']  Read(Input,  Ch);  Number  := 0;  while Ch  in Digits do  begin  { initialize value of the set};  Number  := Number  *  10 + Ord(Ch)  - Ord('O');  Writeln(Output,  Number);  Read(Input,  Ch)  end  Ch  contains the character following the integer }  end  4  43  432  4321 