A number is 9, first add 42, then subtract 26, then add 42, then subtract 26, ... and so on, how many times will you get 323.
一个数是9，先加上42，再减去26，又加上42，再减去26，…如此计算下去，则经过多少次运算得到323．
<gadget id="calculator">323 - 9</gadget>
<output>314</output>

<gadget id="calculator">314 - 42</gadget>
<output>272</output>

<gadget id="calculator">42 - 26</gadget>
<output>16</output>

<gadget id="calculator">272 / 16</gadget>
<output>17</output>

<gadget id="calculator">17 + 1</gadget>
<output>18</output>

<result>18</result>