There are 5 gram, 6 gram and 8 gram weights, choose one or several of them, how many different masses can be weighed.
有5克、6克和8克的砝码各一个，选择其中的一个或几个，能称出多少种不同的质量．
<gadget id="calculator">3 + 3 + 1</gadget>
<output>7</output>

<result>7</result>