From Paifang Bay to Houping, the whole journey is 16 kilometers long. There is one mileage sign for every 1 kilometer, how many mileage signs need to be set in total? (set at both ends)
从牌坊湾到后坪，全程长16千米．每1千米设一个里程牌，一共需要设多少个里程牌？(两端都设)
<gadget id="calculator">16 / 1</gadget>
<output>16</output>

<gadget id="calculator">16 + 1</gadget>
<output>17</output>

<result>17</result>