Xiaofan's home is 800 meters away from the school. One day, Xiaofan came home from school. After walking 200 meters, he found that his homework had been left in the classroom, and he went back to get it. How many meters did Xiaofan walk home from school this time?
小凡家离学校800米．一天小凡从学校放学回家，走了200米后发现作业本丢在了教室，又回去拿，这次小凡从学校回家一共走了多少米．
<gadget id="calculator">200 * 2</gadget>
<output>400</output>

<gadget id="calculator">800 + 400</gadget>
<output>1_200</output>

<result>1_200</result>