993+994+995+996+997+998+999=? How is it easier? Please write down the main process.
993+994+995+996+997+998+999=？怎样算比较简便？请你写出主要过程．
<gadget id="calculator">993 + 994 + 995 + 996 + 997 + 998 + 999</gadget>
<output>6_972</output>

<result>6_972</result>