If two squares with side lengths of 1 cm are used to form a rectangle, what is the perimeter of the rectangle in centimeters?
用两个边长是1厘米的正方形拼成一个长方形，这个长方形的周长是多少厘米．
<gadget id="calculator">1 + 1 + 1</gadget>
<output>3</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<result>6</result>