Dad went on a business trip on May 1, 2008, and came back on September 17. How many days did Dad go on business?
爸爸在2008年5月1日出差，9月17日回来，爸爸出差了多少天．
<gadget id="calculator">31 * 3</gadget>
<output>93</output>

<gadget id="calculator">17 - 1</gadget>
<output>16</output>

<gadget id="calculator">93 + 30 + 16</gadget>
<output>139</output>

<result>139</result>