Calculate with a simple method: 999*444+333*668.
用简便方法计算：999*444+333*668．
<gadget id="calculator">999 * 444</gadget>
<output>443_556</output>

<gadget id="calculator">333 * 668</gadget>
<output>222_444</output>

<gadget id="calculator">443_556 + 222_444</gadget>
<output>666_000</output>

<result>666_000</result>