We will define a number to be "sad", "happy" or "ecstatic" based on the digits of its base-4 representation. If none of these digits in base-4 are 3's the number is sad. If at least one of these digits is a 3 the number is happy. But if ALL the digits in base-4 are 3's the number is ecstatic. Return the correct string based on the positive integer input parameter. See test data for examples.