The school has 156 novels, 78 more science books than novels, and three times the total number of children's story books. How many children's story books does the school have?
学校有小说156本，科技书比小说多78本，儿童故事书是小说和科技书总本数的3倍，学校有多少本儿童故事书？
<gadget id="calculator">156 + 78</gadget>
<output>234</output>

<gadget id="calculator">156 + 234</gadget>
<output>390</output>

<gadget id="calculator">390 * 3</gadget>
<output>1_170</output>

<result>1_170</result>