Specification of mathq program
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mathq is a program that repeatedly presents the user with a series of
simple multiplication and division questions and checks the user's
answers for correctness. The questions involve a single multiplication
or division operation and correspond to the elementary multiplication
table. All multiplication questions will involve two integers in the
range 0-9 inclusive. All division questions will correspond to an
inverse of a legal multiplication question.

The program will be run from the command line, and will display a
welcome message on startup. Questions will be printed to the screen,
and the program will wait for the user to type in an answer. A message
will be displayed indicating if the answer was correct or incorrect.
The correct answer will be displayed. A message will then appear,
asking a new question. If the user inputs a letter q, the program will
terminate. Otherwise, any responses that are not simple integers will
result in an error message, and the question will be redisplayed.