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We assume a two dimensional array is used to store the raw data. Particularly, xs,q (x[s,q]) is the choice made by student s for question q. The choice can be an integer, a letter, or a general string. s is a number representing a student (0 oriented), and q is a number representing a question (0 oriented).
We can also an array is used to store student names so that name[s] is the name of student s. Let us assume numStudent and numQuestion are used to represent the number of students and the number of questions, respectively.