A can of candy, eat half of the total on the first day, eat the remaining half on the second day, and after eating 15 on the third day, there are still 18 candies left. How many pieces of candy are there in this jar? (Hint: You can use the tree diagram to answer)
一罐糖果，第一天吃了总数的一半，第二天又吃了剩下的一半，第三天吃了15粒后还剩下18粒糖．原来这罐糖果共多少粒？(提示：可借助树状算图解答)
<gadget id="calculator">15 + 18</gadget>
<output>33</output>

<gadget id="calculator">33 * 2 * 2</gadget>
<output>132</output>

<result>132</result>