If two squares with a side length of 1 cm are put together to form a rectangle, the perimeter is reduced by how many centimeters.
用两个边长1厘米的正方形拼成一个长方形，周长减少了多少厘米．
<gadget id="calculator">1 * 2</gadget>
<output>2</output>

<result>2</result>