这是关于文件操作的一个题，由题意可知，该题解决起来应该分为三个部分。第一部分即从in.dat中读入数据，第二部分即实现排序的算法，最后应该实现将排序的结果输出到out.dat中。-This is the document on the operation of a title, and that Italy, we can see that the solutions to the problem should be divided into three parts. The first part from in.dat read into the data, the second part of that is to achieve the ranking algorithm, the final order will be to achieve the results were exported to out.dat.