本代码根据google官方文档进行编写，是标准的google广告的代码范例。-The code official documents written according to google, google ads is the standard code examples.

本代码演示了多个admob广告，将其放在enum下，同时取多个admob广告，看其特点。-This code demonstrates a number of admob advertising, put it in the next enum, while taking multiple admob ads, look at its characteristics.