Program texte;
   var litere,simboluri:set of char;
       n,k,suma:longint;
       s:string;
       ch:char;
       f:text;

Begin
    litere:=['A'..'Z','a'..'z']; simboluri:=[chr(1)..chr(128)]-litere;
    n:=0; s:='';
    assign(f,'text.in'); reset(f); read(f,ch);
    While not eof(f) do
      begin
        while ch in simboluri do read(f,ch);
        while ch in litere do
          begin
            read(f, ch);
            s:=s+ch;
          end;
        if length(s) > 0 then
             begin
               n:=n+1;
               suma:=suma+length(s);
               s:='';
             end;
     end;
     k:=suma div n;
  assign(f,'text.out');
   rewrite(f);
     write(f,k);
  close(f);
end.