var f,g:text; s:string; m,k,i:integer;
begin
assign(f, 'text.in'); reset(f);
assign(g, 'text.out'); rewrite(g);
read(f,s);
for i:=1 to length(s) do
if s[i] in ['a'..'z', 'A'..'Z'] then
                                    begin
                                        inc(k);
                                        if not(s[i-1] in ['a'..'z', 'A'..'Z']) and (i<>1) then inc(m);
                                    end;
write(g, trunc(k/m));
close(f); close(g);
end.