a/27=17...b, when the remainder is the largest, what is a?
a/27=17…b，当余数最大时，a是多少．
<gadget id="calculator">17 * 27</gadget>
<output>459</output>

<gadget id="calculator">27 - 1</gadget>
<output>26</output>

<gadget id="calculator">459 + 26</gadget>
<output>485</output>

<result>485</result>