Add 4 to 36, subtract 8, add 4, and then subtract 8... Do this continuously, how many times you do the calculation, the result will be 0.
36加上4，减去8，再加上4，再减去8…这样连续地做下去，做多少次计算结果得0．
<gadget id="calculator">8 - 4</gadget>
<output>4</output>

<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<result>9</result>