?? ?6????19????????
????:1?????????:?????
2?????
3????????????
4???????
5???????????
??6??18?????(????????? ???????????)???18??,??,????????19??
?????,??,??,????????,????????????????????????;???????????
???(???????????)????????? ?? ????????????,???300???~500??,????(?????256?);???,????????150?~200??????????,???
??????????,?????????????7??????,???????????(????)
????:????????