The values for the variables are determined by the homework program, which can be edited online as well. A calculator window helps to check the variable assignments.
Different students see different numbers, the same student always the same numbers.
The syntax for the homework problem is C-like, more advanced programing structures are available. If you tried to solve the homework program two page earlier, you might have noticed that after entering a wrong answer, hints appear. These hints can adapt to the specific wrong answer. Faculty can specify a set of wrong answers, and special hints that appear if that wrong answer was entered. The upper screenshot shows both how the wrong answers are specified and how the hints are given.