【判断题】Decide whether the following paragraphs are unified or not. My father’s face is rough. His complexion is leathery and wrinkled. There are large pores in the skin that covers his nose and cheeks. His n...
【单选题】用PV操作解决读者写者问题的正确程序如下: Begin S,sr:semaphore,rc:integer; S=1,sr=1,rc=0; Cobegin PROCESS reader i(i=1,2,...) Begin p(sr); rc:=rc+1; if rc=1 then p(s); v(sr); read file; p(sr); rc:=rc-1; if rc=0 then v...