corridor is 36 meters long. On one side of the corridor, potted flowers are placed every 3 meters. If no two ends are placed, how many potted flowers are placed in total?
一条走廊长36米，在走廊的一边每隔3米放一盆花，如果两端都不放，一共放了多少盆花．
<gadget id="calculator">36 / 3</gadget>
<output>12</output>

<gadget id="calculator">12 - 1</gadget>
<output>11</output>

<result>11</result>