Lingling has 4 books more than Xiaoli, Xiaoming has 6 books less than Xiaoli, and how many books does Xiaoming have less than Lingling.
玲玲比小丽多4本书，小明比小丽少6本书，小明比玲玲少多少本书．
<gadget id="calculator">10 - 6</gadget>
<output>4</output>

<gadget id="calculator">4 - 4</gadget>
<output>0</output>

<gadget id="calculator">10 + 0</gadget>
<output>10</output>

<result>10</result>