Two squares with side lengths of 1 cm are assembled into a rectangle. What is the perimeter of this rectangle in centimeters.
两个边长是1厘米的正方形，拼成长方形．这个这个长方形的周长是多少厘米．
<gadget id="calculator">1 + 1</gadget>
<output>2</output>

<gadget id="calculator">2 + 1</gadget>
<output>3</output>

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

<result>6</result>