任务旨在强化线程编程能力，对并行所带来的性能优势有直观的认识。

在阅读大型项目代码时，经常要搜索某个标识符，找出该标识符的声明、定义或引用的地方（某文件的哪一行）。本任务要求实现一个程序idfind，其使用格式如下：

idfind [-j n] id dirname

选项 -j 指定并行线程数目。如果省略该选项，则只启动一个线程。

id表示要查找的标识符，dirname表示项目所在目录。-Task is to strengthen the ability of programming, the parallel performance advantages have intuitive awareness.



In reading a large project code, often want to search an identifier, find out the identifier statement, define or reference place (a document which line ). The tasks required to achieve a idfind program, using the following format:



Idfind [-j n] ID dirname



Option-j specifies the number of parallel threads. If you omit the option, only to start a thread.



Id said to find the identifier, dirname said the project directory.