EOF

with Ada.Text_IO;
use Ada.Text_IO;
with Ada.Integer_Text_IO;
use Ada.Integer_Text_IO;
procedure vowelcounter is
   Letter:Character;
   counter:Integer:=0;

begin
   while not End_Of_File loop

      Get(Letter);
      case Letter is
      when 'a'|'e'|'i'|'o'|'u' => counter:=counter+1;
      when others =>
         null;

      end case;
   end loop;
   New_Line;
   Put_Line("you entered " & Integer'Image(counter) & " vowel");
end vowelcounter;