用c 实现的一个命令行的计算器，包含+，-，*，/，有负号，小数点，多位，并且可以加入绝对值，这个有点挑战性，这是我比较自豪的一点（大言不惭啊）。-C achieved by a command line calculator, including+,-,*,/, negative numbers, decimal point, a number, and the absolute value can be added to this a bit challenging, I am rather

求任意两数之和；任意两数之积；求一个数的绝对值；求e的任意指数值；求一个数的对数值-Seeking any two numbers any product of two numbers the absolute value of a number seek any index value e seeking for a number of values