Among the 100 natural numbers from 1 to 100, how many times does the number 1 appear?
在1到100这100个自然数中，数字1共出现多少次．
<gadget id="calculator">1 * 8</gadget>
<output>8</output>

<gadget id="calculator">1 + 11 + 8 + 1</gadget>
<output>21</output>

<result>21</result>