说明：  两个word文件： 1）、C++常用库函数，里边全都是我整理过的。 2）、c++常用数学函数，我把它们列出来了，并给出了简洁的解释
(Two word documents: 1), C++ Common library function, inside all that I have been collated. 2), c++ Common mathematical functions, I put them to the list, and gives a concise explanation)