const litere:set of char=['a'..'z','A'..'Z'];
var f:text; c:char; n,t:longint; inceput:boolean;
begin
assign(f,'text.in');reset(f);
repeat
read(f,c);
if (c in litere) and not(inceput)then begin
                                      inc(n);
                                      inc(t);
                                      inceput:=true;
                                      end
                                 else if inceput and (c in litere) then inc(T)
                                 else inceput:=false;
until eof(f);
close(f);
assign(f,'text.out');
writeln(f,t div n);
close(f);

end.