From the first page to the last page of "Folk Tales", 357 numbers are used to mark the page numbers. How many pages does this book have?
《民间故事》第一页到最后一页共用了357个数字来标注页码，这本书有多少页？
<gadget id="calculator">156 - 1</gadget>
<output>155</output>

<result>155</result>