cut in the middle of a cuboid becomes two cubes, and the surface area increases by 18 square centimeters. What is the sum of the lengths of the sides of the original cuboid in centimeters?
把一个长方体中间切一刀，就变成两个正方体，表面积增加了18平方厘米，原长方体的棱长总和是多少厘米．
<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">3 + 3 + 6</gadget>
<output>12</output>

<gadget id="calculator">12 * 4</gadget>
<output>48</output>

<result>48</result>