An express train from Beijing to Shanghai has to stop at 8 stations on the way. How many different tickets should the station prepare for this train?
一辆从北京到上海的快运列车，中途要停靠8个站，车站要为这趟列车准备多少种不同的车票．
<gadget id="calculator">8 + 2</gadget>
<output>10</output>

<gadget id="calculator">10 - 1</gadget>
<output>9</output>

<gadget id="calculator">10 * 9</gadget>
<output>90</output>

<result>90</result>