There are 78 pine trees, and there are 12 fewer pine trees than twice as many cypress trees. How many cypress trees are there in the forest?
松树有78棵，松树比柏树的2倍少12棵，树林里柏树有多少棵？
<gadget id="calculator">78 + 12</gadget>
<output>90</output>

<gadget id="calculator">90 / 2</gadget>
<output>45</output>

<result>45</result>