个人和结对项目 - 英语单词词频统计

个人或结对编程项目 英语单词词频统计程序

 (最新版本在这里)

实现一个命令行程序，支持几种模式下的单词词频统计

Implement a console application to tally the frequency of words under a directory.

For all text files (file extension: "txt") under a directory (recursively), calculate the frequency of each word, and output the result into a text file.  

2 options to write the program:

    a) Write the code in C++ or C#, using .Net Framework, the running environment is 32-bit Win7 or Win10. with VS studio 2012-2015 profiling tool

    b) Write the code in Java, using latest JDK, run it on Win10, or Linux platform with appropriate Java profiling tool

Run performance analysis tool on your code, find performance bottlenecks and improve.

Enable Code Quality Analysis for your code and get rid of all warnings.

Code Quality Analysis:  http://msdn.microsoft.com/en-us/library/dd264897.aspx 

Write 10 simple test cases to make sure your program can handle these cases correctly (e.g.  a good test case could be: one of the sub-directories is empty).

Submission:

Submit your source code and exe to TA, TA will run it on his testing environment and check for

       - correctness   (incorrect program will get 0 points)

       - performance

       - write a blog (see blog requirement below)

Definition:

A word: a string starting with one English alphabet letters, then followed by optional alphanumerical characters.  Words are separated by delimiters. If a string contains non-alphanumerical characters, it’s not a word. Word is case insensitive, i.e. “file”, “FILE” and “File” are considered the same word.

“file123” is a word, and “123file” is NOT a word.

　　- Alphabetic letters:  A-Z, a-z.

　　- Alphanumerical characters: A-Z, a-z, 0-9.

　　- Delimiter: space, non-alphanumerical letters.

　　- Output text file: filename is <your email name>.txt

　　- Each line has this format

　　　　　　<word>: number

Where <word> is the string, showing in all upper-case format.  E.g. if only “File” and “file” appear in the test file,  the program should show “FILE”.

Where “number” is the number of times this word appears in the file(s)  The output should be sorted with most frequent word first.  If 2 words have the same frequency, list the words by dictionary order.

Requirements:

1)      Simple mode.   Output simple word frequency.

Myapp.exe <directory-name>

Will output <your-name>.txt file in current directory, the text file contains word ranking list.

2)      Extended mode. 

在执行 Myapp.exe -e2 <directory-name>时，找出最频繁出现的连续两个词(列出前10名)。例如，在一本英文小说中，“good morning” 出现次数最多。

在执行 Myapp.exe -e3 <directory-name>时，找出最频繁出现的连续三个词(列出前10名)。例如“how are you"。

这里连续的词是指由单个空格分隔的词。

The app will output <your-name>.txt file in current directory, the text file contains word ranking list.

3)      support -v, verb tally mode. 

Myapp.exe -v <directory-name>时，找出最频繁出现的动词，包括这个动词出现的各种变态。

在学习英语的过程中我们学习过很多动词，知道动词有原型，和各种时态/语态下的变形。 例如：

原型： do

变形：does, did, done, doing.

那么，一篇英语文章里， 有多少个动词”do” 和它的各种变形呢？ 最频繁的动词前10名是什么呢？这就是我们这个练习的目的。

任务分解：

1)自己构造(或者助教提供)一个动词及其变形的文本文件。 每一行开头是原型，后面跟着各种变形，例如：

     do does did done doing

     get gets got gotten getting

     ...

2) 处理

　　Myapp.exe -v <directory-name>

    对于每一个符合条件的文件处理， 然后统计出所有文件中最频繁动词的前10名。

Blog Requirement:

You can publish this to BOTH your own blog, and your team blog (to help your team blog get some traffic)

1)      Before you implement this project, Record your estimate about the time you WILL spend in each component of your program.

2)      After you had implemented this project, record the ACTUAL time you spent in each component of your program.

3)      Describe how much time you spent on improving the performance of your program, and show a performance analysis graph (generated by VS2012 perf analysis tool), if possible, please show the most costly function in your program.

4)      Share your 10 test cases, and how did you make sure your program can produce the correct result. (programs with incorrect result will get 0 points,  regardless of speed)

5)      Describe what you had learned in this exercise.