The sum of numbers in 1997 is 1+9+9+7=26. Among the four-digit numbers less than 2000, how many four-digit numbers have the sum equal to 26?
1997的数字和是1+9+9+7=26，小于2000的四位数中，数字和等于26的四位数共有多少个．
<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<result>6</result>