???????????????????
??????????????????????????????к?????????????磺??в?????()?????
????A???????? B????????C????????D????????????
?????????Щ?1?????????????????????磺????????????????()(??????)??????????????????????????(???????????????????????????????)????μ???C ?????????磺???????????????()
????float a=1.of;
????cout<<(int)a< cout<<(int&)a< cout< ??????????4 ??????12 ??
???????????????
????1??????????????4 ???????????????
????2??main(){int *piPointer;char cItem;cItem='a';piPointer=(int *)&cItem;*piPointer=1298;}
??????????????δ????е????????????????????????????
????????????????????15 ??
?????????????????????????дsql ???
?????????????????γ????????
????1????SQL ??佨??????????????????????????????
????2?????????????20-23 ????????
????3??????avg
????4??????update