There are 33 apples, distributed to 4 people A, B, C, and D. Each person is given at least one apple, and no more than 9. How many different possibilities are there in total?
有33个苹果，分给甲、乙、丙、丁4个人，每个人最少分一个苹果，不超过9个，一共有多少种不同的可能．
<gadget id="calculator">4 + 12 + 4</gadget>
<output>20</output>

<result>20</result>