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Dipartimento di Elettronica, Informazione e Bioingegneria Politecnico di Milano Prof. Elisabetta Di Nitto and Matteo Rossi 20133 Milano (Italia) Piazza Leonardo da Vinci, 32 Tel. (39) 02-2399.3400 Fax (39) 02-2399.3411 Software Engineering II September 13th, 2018 Last Name First Name Id number (Matricola) Note 1. The exam is not valid if you do not fill in the above data. 2. Write your answers on these pages. Extra sheets will be ignored. You may use a pencil. 3. Incomprehensible hand-writing is equivalent to not providing an answer. 4. The use of any electronic apparatus (computer, cell phone, camera, etc.) is strictly forbidden. 5. You cannot keep a copy of the exam when you leave the room. 6. The exam is composed of three exercises. Read carefully all points in the text! 7. Total available time: 2h Scores of each question: Question 1 (MAX 8) _________ Question 2 (MAX 8) _________ Question 3 (MAX 3) _________ 2 Question 1 Alloy (8 points) Consider an application that recommends to users what movies to rent or buy; the application, given the history of rentals and buys of the user, recommends what other movies could be of interest for her/him. Given the application outlined above, consider the following world phenomena: • Every user has seen some movies. • Every user likes some movies (it is not necessary that a user has seen a movie that she/he likes; also, a user might have seen movies that she/he does not like). Consider also the following shared phenomena: • Each user has bought some movies. • Each user has rented some movies. • Each user rates as excellent, good, or bad every movie she/he has bought or rented. Finally, consider the following machine phenomena: • Each movie has a set of movies that are similar in nature; the notion of “similarity” is symmetric (if…