Bajie went to sell watermelons, on the first day he sold half of the total and two more, on the second day he sold the remaining half and two more, on the third day he sold the remaining half and two more, leaving two. How many watermelons are there in this pile?
八戒去卖西瓜，第一天卖出总数的一半多两个，第二天卖出余下的一半多两个，第三天卖出剩余的一半又两个，还剩2个．这堆西瓜共多少个？
<gadget id="calculator">2 + 2</gadget>
<output>4</output>

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

<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<gadget id="calculator">10 * 2</gadget>
<output>20</output>

<gadget id="calculator">20 + 2</gadget>
<output>22</output>

<gadget id="calculator">22 * 2</gadget>
<output>44</output>

<result>44</result>