A book has a total of 198 pages. When typesetting, one typeface can only place one number. How many typefaces are used to arrange the page numbers of this book?
一本书共198页，排版时一个铅字只能排一位数字，那么排这本书的页码共用了多少个铅字？
<gadget id="calculator">90 * 2</gadget>
<output>180</output>

<gadget id="calculator">98 + 1</gadget>
<output>99</output>

<gadget id="calculator">99 * 3</gadget>
<output>297</output>

<gadget id="calculator">9 + 180 + 297</gadget>
<output>486</output>

<result>486</result>