const
 ToFind = ['б', 'в', 'г', 'д', 'ж', 'з'];
var
 Found: set of char;
 s: string; i: byte;
 lett: char;
begin
 write('s = '); readln(s);
 for i := 1 to length(s) do
   if s[i] in ToFind Then Found := Found + [s[i]];

 For lett := 'а' to 'я' do
   if lett in Found then write(lett, ' ');
end.