In the mathematics activity class, the chess pieces around Xiaohua were arranged in a hollow square. There are 16 chess pieces on each side of the outermost layer and 8 chess pieces on each side of the innermost layer. How many chess pieces are there in total in this hollow square array?
在数学活动课上，小华同学周围棋子排成了一个空心方阵，最外层每边有16枚棋子，最内层每边有8枚棋子，这个空心方阵一共有围棋子多少枚？
<gadget id="calculator">16 * 4</gadget>
<output>64</output>

<gadget id="calculator">64 - 4</gadget>
<output>60</output>

<gadget id="calculator">8 * 4</gadget>
<output>32</output>

<gadget id="calculator">32 - 4</gadget>
<output>28</output>

<gadget id="calculator">28 + 8</gadget>
<output>36</output>

<gadget id="calculator">36 + 8</gadget>
<output>44</output>

<gadget id="calculator">44 + 8</gadget>
<output>52</output>

<gadget id="calculator">60 + 52 + 44 + 36 + 28</gadget>
<output>220</output>

<result>220</result>