标签：
http://stackoverflow.com/questions/588004/is-floating-point-math-broken
http://stackoverflow.com/questions/3730019/why-not-use-double-or-float-to-represent-currency/3730040#3730040
https://en.wikipedia.org/wiki/Floating_point
研究float的一些好文章
原文地址：http://my.oschina.net/u/2291753/blog/505898
