Mom made a cloth cover for the air conditioner at home. The length of the air conditioner is 78 cm, the width is 12 cm, and the height is 25 cm (no cloth is used on the side next to the wall).
妈妈给家里的空调做一个布罩，空调长78厘米，宽12厘米，高25厘米(靠墙的一面不用布)，做这个布罩至少需用多少布？
<gadget id="calculator">78 * 12</gadget>
<output>936</output>

<gadget id="calculator">78 * 25</gadget>
<output>1_950</output>

<gadget id="calculator">12 * 25</gadget>
<output>300</output>

<gadget id="calculator">936 + 1_950 + 300</gadget>
<output>3_186</output>

<gadget id="calculator">3_186 * 2</gadget>
<output>6_372</output>

<gadget id="calculator">6_372 - 1_950</gadget>
<output>4_422</output>

<result>4_422</result>