Homework Assignment 1 Solution

Description

Collaboration Policy. Homeworks will be done individually: each student must hand in their own answers. It is acceptable for students to collaborate in understanding the material but not in solving the problems or programming. Use of the Internet is allowed, but should not include searching for existing solutions.

Under absolutely no circumstances code can be exchanged between students. If some code was shown in class, it can be used, but it must be obtained from Canvas, the instructor or the TA.

Assignments from previous offerings of the course must not be re-used. Violations will be penalized appropriately.

Late Policy. No late submissions will be allowed without consent from the instructor. If urgent or unusual circumstances prohibit you from submitting a homework assignment in time, please e-mail me.

MovieLens Datasets Data for this assignment should be obtained from: http://grouplens. org/datasets/movielens/

You should use the following datasets for all problems:

1. 100,000 ratings from 1000 users on 1700 movies. Released 4/1998.

2. 1 million ratings from 6000 users on 4000 movies. Released 2/2003.

3. 10 million ratings and 100,000 tag applications applied to 10,000 movies by 72,000 users. Released 1/2009.

u.data: Data are stored as strings separated by a tab (nt):

user id item id rating timestamp

For example:

2. Use comments where necessary to explain what you are doing. No comments or over-commenting are both bad.

2. Use functions! Do not place all your code in main().

2. Do not leak memory. Free all allocated memory and close all opened files.

2. Try to use only material covered in the course this far.

Deliverables. A zip/tar/gz file containing:

1. text2bin.c

2. bin2text.c

3. bin2indexed.c

4. A pdf file with brief explanations of your approach and timing results.

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