23 students are going on a spring outing. If they want to be divided into groups of 3 or 5, there will be no leftovers. At least how many students do we need to add?
23名同学去春游，如果想分成3人一组或5人一组都不剩余，最少还需要加几名同学？
<gadget id="calculator">30 - 23</gadget>
<output>7</output>

<result>7</result>