program infoarena1;
var f,g:text;
    c:char;
    litere,cuvinte:longint;
    s:string;
    bufin,bufout:array[1..660000] of byte;
begin
   assign(f,'text.in'); reset(f);
   assign(g,'text.out'); rewrite(g);
   settextbuf(f,bufin);
   settextbuf(g,bufout);
   litere:=0; cuvinte:=0;
   s:='QWERTYUIOPASDFGHJKLZXCVBNMqwertyuiopasdfghjklzxcvbnm';
   while not eof(f) do
      begin
      read(f,c);
      if pos(c,s) > 0  then
         begin
         inc(cuvinte);
         while pos(c,s) > 0 do
            begin
            inc(litere);
            read(f,c);
            end;
         end;
      end;
   writeln(g,litere div cuvinte);
   close(f); close(g);
end.