A book has 320 pages, how many codes are shared from page 1 to page 320 after coding.
一本书有320页，从第1页到第320页编码后，共用去多少个数码．
<gadget id="calculator">2 * 90</gadget>
<output>180</output>

<gadget id="calculator">320 - 100</gadget>
<output>220</output>

<gadget id="calculator">220 + 1</gadget>
<output>221</output>

<gadget id="calculator">221 * 3</gadget>
<output>663</output>

<gadget id="calculator">9 + 180 + 663</gadget>
<output>852</output>

<result>852</result>