Draw 30 straight lines on a circular piece of paper, how many small pieces can it be divided into at most?
在一张圆形纸片中画30条直线，最多能把它分成多少小块．
<gadget id="calculator">30 + 1</gadget>
<output>31</output>

<gadget id="calculator">30 / 2</gadget>
<output>15</output>

<gadget id="calculator">31 * 15</gadget>
<output>465</output>

<gadget id="calculator">1 + 465</gadget>
<output>466</output>

<result>466</result>