In the natural numbers from 1 to 1000, how many numbers appear 2 or 4.
从1到1000的自然数中，有多少个数出现2或4．
<gadget id="calculator">36 * 8</gadget>
<output>288</output>

<gadget id="calculator">100 * 2</gadget>
<output>200</output>

<gadget id="calculator">288 + 200</gadget>
<output>488</output>

<result>488</result>