Grandpa Zhang’s house has a chicken coop against the wall, the length and width are 4 meters and 2 meters respectively. If a chicken coop is fenced, what is the minimum length of the fence needed for the chicken coop?
张爷爷家有一个靠墙的鸡舍，长和宽分别是4米和2米．如果用篱笆围鸡舍，这个鸡舍至少需要多长的篱笆？
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">4 + 4</gadget>
<output>8</output>

<result>8</result>