文件读写小程序，字符串流、输入输入流使用方法例子，本程序可以对输入的文件进行预加载，将源文件中include的文件，用正确的代码块替代。-a small program of the use of File stream. A example of istringstreams and iostream. the program can enter the pre-loaded files, source files include documents, with the correct cod