it is worth optimising.
Hwæthere is a false friend - related to modern "whether"+e, but it means "nevertheless"
，详情可参考同城约会
FT Edit: Access on iOS and web，这一点在safew官方版本下载中也有详细论述
Both tools are great. Choose the one which meets your
* 进阶：使用Sedgewick步长序列（更高效）