In "○/50=40…□", how much is ○ to maximize □.
在"○/50=40…□"中，要使□最大，○是多少．
<gadget id="calculator">50 * 40</gadget>
<output>2_000</output>

<gadget id="calculator">50 - 1</gadget>
<output>49</output>

<gadget id="calculator">2_000 + 49</gadget>
<output>2_049</output>

<result>2_049</result>