Xiaogang swam back and forth twice in a 35-meter-long swimming pool. How many meters did he swim in total?
小刚在长35米的游泳池里来回游了2个来回，他一共游了多少米．
<gadget id="calculator">35 * 2 * 2</gadget>
<output>140</output>

<result>140</result>