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Problem 1:
File I/O testing

• Write this as a script file and run it from the command line
• Use a text file (more than 5000 characters).
• Process the following commands
• Filter the data and find the frequency at which the ascii chars appear ([a-z,A-Z], [0-9]).
• Store the results in a dictionary.
• Emulate the Unix command "wc" to get the number of lines, #words, #chars
  
• Find the top 50 words (most frequently ocurring) on this Web page, print them out in sorted order and reverse order.
  

note: you will reuse these in Problem 3. use the list, tuple, and dictionary objects in this problem.


Problem 2:   
An ice cream store sells M flavours of ice cream. You want to buy N dishes of ice cream.

• Write a script to find all the different ways in which you can fulfill your purchase.  Use recursion to compute  the permutations.
  
• Assume:
• M > N
• Each dish has one scoop
• Each combination of dishes is unique
• Write the script as a module and import it into the interpretor and run it.
• Save results to a file
  
• Test your code for different values of M, for (N<M, N=M, N>M).

Problem 3: 
The TeraGrid (http://www.teragrid.org) hosts information and resources for the NSF computational science community. The TeraGrid User Portal provides  dynamics information about comuptational  and archival systems:

• Use "HTML Scraping" to dynamically read the contents of this Web page.
• Filter the data and identify "words" using common "white space" filters (blanks, CR, etc.)
• you can make the filter case insensitive
• hint: look for ascii words like 'the', 'teragrid'
• Emulate the Unix command "wc":
• Find the top 20 words on this Web page.
  

HINT: Google for the term "HTML Scraping" and  the Python modules urllib and popen2