How many decimeters are left to make a square with a side length of 2 decimeters using a 1 meter long iron wire?
用一根一米长的铁丝做一个边长为2分米的正方形，还剩多少分米？
<gadget id="calculator">1 * 10</gadget>
<output>10</output>

<gadget id="calculator">2 * 4</gadget>
<output>8</output>

<gadget id="calculator">10 - 8</gadget>
<output>2</output>

<result>2</result>