This year's summer vacation starts on June 28 and ends on August 31. How many days are there in total?
今年暑假从6月28日开始，8月31日结束，暑假一共有多少天．
<gadget id="calculator">30 - 28</gadget>
<output>2</output>

<gadget id="calculator">2 + 1</gadget>
<output>3</output>

<gadget id="calculator">3 + 62</gadget>
<output>65</output>

<result>65</result>