A train from Nanchang to Jingdezhen has to stop at 3 stations with different distances. How many fares are there?
从南昌到景德镇的一列列车中途要停3个路程不同的站点，有多少种票价．
<gadget id="calculator">4 + 3 + 2 + 1</gadget>
<output>10</output>

<result>10</result>