Among all four-digit numbers, how many numbers are there in which the sum of the digits equals 34?
在所有四位数中，各位上的数之和等于34的数有多少种．
<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">6 + 4</gadget>
<output>10</output>

<result>10</result>