A cylindrical steel bar is cut into 3 sections, how many bases are the surface area increased?
一根圆柱形钢材横截成3段，表面积增加了多少个底面．
<gadget id="calculator">3 - 1</gadget>
<output>2</output>

<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<result>4</result>