Program texte;
   var litere,simboluri:set of char;
       ch:char;
       suma,cuvinte:longint;
       f:text;
begin
  assign(f,'text.in'); reset(F); read(f,ch);
  litere:=['a'..'z','A'..'Z']; simboluri:=[chr(1)..chr(127)]-litere;
   suma:=0; cuvinte:=0;
  while not eof(f) do  begin
     while not eoln(f) do begin
       while ch in simboluri do read(f,ch);
       if ch in litere then begin
                             inc(cuvinte);
                             while ch in litere do
                               begin
                                 inc(suma);
                                 read(f,ch);
                               end;
                               end;
       end;
       readln(f);
     end;
    close(f); assign(f,'text.out'); rewrite(f);
    writeln(f,suma div cuvinte); close(f);
end.