简单计算器，可计算三角函数，支持科学计算，和简单运算-Simple calculator, calculate trigonometric functions in support of scientific computing, and simple operation

计算器源代码c,和windows自带的功能差不多,很多科学计算还没有加入,(Calculator source code, c is similar to Windows's own functions, a lot of scientific computing has not joined,)