There is a box of pears, A takes half and one pear, B takes the remaining half and one, C takes the remaining half and one, and there is only one pear left in the box. How many pears are there in this basket?
有一框梨，甲取了一半又1个，乙取了余下的一半又1个，丙又取了余下的一半又1个，这是框里只剩1个梨．这筐梨共有多少个？
<gadget id="calculator">1 + 1</gadget>
<output>2</output>

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

<gadget id="calculator">4 + 1</gadget>
<output>5</output>

<gadget id="calculator">5 * 2</gadget>
<output>10</output>

<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<gadget id="calculator">11 * 2</gadget>
<output>22</output>

<result>22</result>