编写一段程序创建两个子线程，分别对两个文件的字数进行统计，两个线程统计完后写入子线程与父线程共享的一块内存中，然后父线程从这一块内存中读取相应的信息。注意线程的同步和互斥。-Procedures for the preparation of a section of the creation of two sub-threads, respectively, the number of words on the two documents to statistics, the two threa