Suppose (147/340)=(1/(a+(1/(b+(1/(c+(1/(d))))))), where a, b, c, and d are all non-zero natural numbers, then a+b+c+d=how much.
设(147/340)=(1/(a+(1/(b+(1/(c+(1/(d))))))))，其中a、b、c、d都是非零自然数，则a+b+c+d=多少．
<gadget id="calculator">2 + 3 + 5 + 9</gadget>
<output>19</output>

<result>19</result>