Pack two cuboid objects of the same size, the length of which is 20 cm, the width is 18 cm, and the height is 4 cm. How to pack with the least amount of wrapping paper? What is the minimum square centimeter of wrapping paper?
把两个相同规格的长方体物品包在一起，物品的长为20厘米，宽为18厘米，高为4厘米．怎么包装用的包装纸最少？最少用多少平方厘米的包装纸？
<gadget id="calculator">20 * 18</gadget>
<output>360</output>

<gadget id="calculator">20 * 4</gadget>
<output>80</output>

<gadget id="calculator">18 * 4</gadget>
<output>72</output>

<gadget id="calculator">360 + 80 + 72</gadget>
<output>512</output>

<gadget id="calculator">512 * 2 * 2</gadget>
<output>2_048</output>

<gadget id="calculator">20 * 18 * 2</gadget>
<output>720</output>

<gadget id="calculator">2_048 - 720</gadget>
<output>1_328</output>

<result>1_328</result>