There are 1 gram, 2 gram, 5 gram and 10 gram weights each, choose one or several of them, how many objects with different masses can be directly weighed on the balance.
有1克、2克、5克和10克的砝码各一个，选其中的一个或几个，能在天平上直接称出多少种不同质量的物体．
<gadget id="calculator">6 + 4 + 4 + 1</gadget>
<output>15</output>

<result>15</result>