Based on the context of the question and the UI of the testing interface, fractions seem unlikely to be an intended part of the question. I likewise wouldn't bother testing unicode U+216x roman numerals.
It refused to accept both fractions and imaginary numbers. I did test negatives and zeros since that was really the only remaining set I could think of.
Most importantly I used about 6 tests (3 right 3 wrong) to come up with the answer and then did another 17 looking for the trick. After all, it couldn't just be that simple right?
Most importantly I used about 6 tests (3 right 3 wrong) to come up with the answer and then did another 17 looking for the trick. After all, it couldn't just be that simple right?