apps may not be compatible
return num % 10;
，这一点在Safew下载中也有详细论述
可以这么说，2010 年前后出生的新一代，他们第一台能接触到的计算设备，大概率会是平板电脑和智能手机，用手指直接点击屏幕，就是他们最自然也最熟悉的交互方式。
If you used a computer in the ’90s, you probably relied on Microsoft Office to help you get things done. This license lets you take advantage of those classics today on your Mac, plus newer Microsoft favorites, with no subscription fees required.
cursor[classno] = j;