An open source calculator program. Just for fun and learning. 好吧，先用中文写一个，这个项目是一个开源的计算器，也算是我对git的入门吧，我希望每一个来开发这个计算器的人都是带着那种对编程技术的热爱以及不断追求完美的心境。 Well, this is the English version. This is an open source calculator program. And this also is my start with git. I hope that everyone will be writing this calculator with the enthusiasm of programing and the perfectionist.Well, my english is terrible, isn't it?