There is a corridor where flowers are placed on both sides from the beginning to the end. A pot of flowers is placed every 2 meters, and there are 50 pots in total. How long is this corridor?
有一条走廊从头到尾两边都要摆花，每隔2米摆一盆花，一共摆了50盆．这条走廊有多长？
<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">25 - 1</gadget>
<output>24</output>

<gadget id="calculator">24 * 2</gadget>
<output>48</output>

<result>48</result>