The IQs of 12 kinds of animals are 12 continuous natural numbers, among which 9 kinds of animals have one each, and the other 3 kinds of animals have 2, 3 and 4 respectively. The IQ sum of these 18 animals is 216. What is the maximum value of the highest IQ?
12种动物的智商为12个连续自然数，其中9种动物各有一只，另3种动物分别为2只、3只和4只．这18只动物的智商和为216．其中最高智商的最大值为多少．
<result>19</result>