program infoarena1;
var f,g:text;
    c:char;
    litere,cuvinte,lungime:longint;             //litere = m ; cuvinte = K; lung = aux
    s:string;
    bufin,bufout:array[1..660000] of byte;
function liter(c:char):boolean;
begin
        liter:= ((c <= 'z') and (c >= 'a')) or ((c <='Z') and (c >= 'A'));
end;
begin
   assign(f,'text.in'); reset(f);
   assign(g,'text.out'); rewrite(g);
   settextbuf(f,bufin);
   settextbuf(g,bufout);
   litere:=0; cuvinte:=0; lungime:=0;
   s:='QWERTYUIOPASDFGHJKLZXCVBNMqwertyuiopasdfghjklzxcvbnm';
   while not seekeof(f) do
        begin
           read(f,c);
           if liter(c) then inc(lungime)
                else
                if (lungime > 0) then
                        begin
                        inc(cuvinte);
                        litere:=litere+lungime;
                        lungime:=0;
                        end;
        end;
   if lungime <> 0 then
        begin
        inc(cuvinte);
        litere:=litere+lungime;
        end;
   writeln(g,litere div cuvinte);
   close(f); close(g);
end.