A room is 6 meters long, 4 meters wide, and 2.5 meters high. It is necessary to paint green paint with a height of 1 meter on the four walls of the room (the door is 1 square meter without painting), how many square meters is the painted area?
一个房间长6米，宽4米，高2.5米，要在房间的四面墙壁上涂1米高的绿色油漆(门1平方米不刷)，涂油漆的面积是多少平方米．
<gadget id="calculator">6 * 1 * 2</gadget>
<output>12</output>

<gadget id="calculator">4 * 1 * 2</gadget>
<output>8</output>

<gadget id="calculator">8 - 1</gadget>
<output>7</output>

<gadget id="calculator">12 + 7</gadget>
<output>19</output>

<result>19</result>