A total of 80 small red flags were planted along the circular lawn, and a potted flower was placed between each two small flags. How many potted flowers should be placed in total.
沿圆形草坪一周共插了80面小红旗，每两面小旗之间摆放一盆花，一共要摆放多少盆花．
<gadget id="calculator">80 * 1</gadget>
<output>80</output>

<result>80</result>