small cube with a side length of 1 cm is cut out from the top center of a large cube with a side length of 3 cm. What is the surface area of this big cube in square centimeters?
在一个棱长为3厘米的大立方体的顶部中央挖去一个棱长为1厘米的小正方体，现在这个大立方体的表面积是多少平方厘米．
<gadget id="calculator">3 * 3 * 6</gadget>
<output>54</output>

<gadget id="calculator">1 * 1 * 4</gadget>
<output>4</output>

<gadget id="calculator">54 + 4</gadget>
<output>58</output>

<result>58</result>