During the Spring Festival this year, the Cultural Center held an art exhibition. From February 15th to the end of February, how many days did the art exhibition last?
今年春节期间文化馆举办了画展，从2月份15日开始至2月底结束，画展共展出了多少天．
<gadget id="calculator">28 - 15</gadget>
<output>13</output>

<gadget id="calculator">13 + 1</gadget>
<output>14</output>

<result>14</result>