var fin,fout:text;
    s:string;
    cuv:longword;
    lit,l,i:longword;
    sant:boolean;

begin
  assign(fin,'text.in'); reset(fin);
  cuv:=0;
  lit:=0;
  sant:=true;

  read(fin,s);
  while  eof(fin)=false do
  begin
    l:= length(s);
    for i := 1 to l do
    begin
      if ((ord(s[i])>$40) and (ord(s[i])<=$5A)) or ((ord(s[i])>$60) and (ord(s[i])<=$7A)) then
      begin
        inc(lit);
        if sant = true then
        begin
          inc(cuv);
          sant:=false;
        end;
      end
      else
        sant:=true;
    end;
    read(fin,s);
  end;

  if cuv <>0 then
    lit:= lit div cuv
  else
    lit:=0;
  close(fin);
  assign(fout,'text.out'); rewrite(fout);
  write(fout,lit);
  close(fout);
end.