建立一个工程，主线程负责用户交互，界面上提供一个按钮，通过它用户建立一个新的线程处理复杂的计算。多个线程可以共享内存中的某些变量。线程可以中止，挂起。线程间需要同步-Set up a project, the main thread is responsible for user interaction, provide a button on the interface through which users set up a new thread to handle complex calc