比起对人体工学的担忧，现在摆在苹果面前的是另一个问题——如果继续拒绝触控，体验反而会割裂。
self.user_agents = [
，这一点在一键获取谷歌浏览器下载中也有详细论述
// Shell原始步长序列: n/2, n/4, ..., 1
Count unique parameters (after weight tying/deduplication)
And though most scientists hail vaccines as one of public health’s greatest achievements, they have provoked fear, distrust, and contentious resistance since Edward Jenner invented the first vaccine, to prevent smallpox, in the late 1700s.