实现字节翻转的两种方法，各有所长。一个函数，只能翻转int型，但效率高。另一个函数模板，能实现 int、float、double等基本数据类型的字节翻转，但效率略低。-Byte flip realize the two methods have their own strong points. A function can only be turned int type, but high efficiency. Another function template can realize int