Calculator443

代码说明：

  一个简单的计算器两个类。还只是完成＋、－、×、÷运算而已。GUI只是用了AWT，很简单，相信一看就能懂了(A simple two-type calculator. Only just completed+,-,×,÷ computing. GUI only used the AWT, is very simple, I believe will be able to understand a look)