subroutine IsEmpty (s$)
	if length(s$) = 0 then
		print "String is empty"
	else
		print "String is not empty"
	end if
	if s$ = "" then print "yes, the string is empty"
	if s$ <> "" then print "no, the string is not empty"
end subroutine

t$ = ""
call IsEmpty (t$)
u$ = "not empty"
call IsEmpty (u$)
end