func (s *Iterator) Seek(target []byte) {
	s.n, _ = s.list.findNear(target, false, true) // find >=.
}
func (s *Iterator) Seek(target []byte) {
	s.n, _ = s.list.findNear(target, false, true) // find >=.
}
// Seek advances to the first entry with a key >= target.