The telephone number of a certain city is increased from 7 digits to 8 digits. Due to special needs, the telecommunications department has always stipulated that the first digits of ordinary city telephone numbers do not use the three digits 0, 1, and 9. After the upgrade, the city's telephone number capacity is tens of thousands.
某市电话号码由7位升至8位．由于特殊需要，电信部门一直有这样的规定：普通市内电话号码的首位数字不使用0、1、9这三个数字．升位后该市电话号码容量为多少万门．
<gadget id="calculator">7 * 10 * 10 * 10 * 10 * 10 * 10 * 10</gadget>
<output>70_000_000</output>

<gadget id="calculator">70_000_000 / 10_000</gadget>
<output>7_000</output>

<result>7_000</result>