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Dipartimento di Elettronica, Informazione e Bioingegneria Politecnico di Milano Prof. Elisabetta Di Nitto, Matteo Rossi 20133 Milano (Italia) Piazza Leonardo da Vinci, 32 Tel. (39) 02-­2399.3400 Fax (39) 02-­2399.3411 Software Engineering II January 24th, 2018 Last Name First Name Id number (Matricola) Note 1. The exam is not valid if you don’t 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! 2 Question 1 Alloy (7 points) NB: Please read the whole exercise text (including the remarks) before starting to work at your solution. Describe through an Alloy model the setup and main operations of the game of bingo (the British version of “tombola”). When a game of bingo is played, a coordinator draws numbers from a bag and places them on a board, to keep track of the fact that they have been drawn (so they cannot be drawn again). Each participant is given one or more tickets consisting of 15 different numbers, arranged along 3 rows (5 numbers per row), as in the following example: The game stops when all 15 numbers appearing on a ticket have been drawn. This is called “bingo” and the owner of the ticket wins a prize. During the game, other prizes are assigned when various combinations of the numbers in a ticket are drawn. For simplicity, we consider only the case “5-in-a-row” that occurs when a row in a ticket is completed (i.e., all its 5 numbers have been drawn). You are required to describe: • A…