There are 10 candles in the room. A gust of wind blows and extinguishes 2 candles. After a while, 1 candle goes out again. To prevent the candles from going out again, close the doors and windows quickly, and no more candles go out. How many candles are left in the room at the end.
房间里有10枝蜡烛，一阵风吹来，熄灭了2枝，一会儿又熄灭了1枝，为防蜡烛再次熄灭，赶紧关紧门窗，再也没有蜡烛熄灭．最后房间里还有多少只蜡烛．
<gadget id="calculator">1 + 2</gadget>
<output>3</output>

<result>3</result>