program setExample (input, output);

type CharSetType = set of char;

letters = array [1..50] of char;

const EMPTY = [];

VOWELS = ['A','E','I','O','U'];

var current, j: char;

set1, set2 : CharSetType;

letterArray : letters;

i : integer;

begin

set1 := EMPTY;

set2 := Vowels;

set1 := set1 + set2;

if ('A' in set1) then

writeln (' A is in set1 ')

else

writeln (' A is not in set1');

set1 := set1 - ['A'];

if ('A' in set1) then

writeln (' A is in set1 ')

else

writeln (' A is not in set1');

i := 0;

writeln (' please enter a word and hit return ');

while not eoln do

begin

read (current);

letterArray[i] := current;

i := i + 1;

set1 := set1 + [current];

end;

for j := 'a' to 'z' do

if (j in set1) then

writeln ( j , ' found in set1 ');

end.