原文链接 http://woodrat.xyz/2014/12/08/%e6%93%8d%e4%bd%9c%e7%b3%bb%e7%bb%9f%e6%a8%a1%e6%8b%9f%e5%ae%9e%e9%aa%8c%e8%bf%9b%e7%a8%8b%e8%b0%83%e5%ba%a6fcfs/
注：以下为加速网络访问所做的原文缓存，经过重新格式化，可能存在格式方面的问题，或偶有遗漏信息，请以原文为准。
简陋的FCFS实现
# -- coding: utf-8 -- class Pcb(object): def init(self): self.pid = None self.ppid = None # id of parent self.arrive_time = 0 self.need_time = 0 self.pprio = 0 #priority
def set_pid(self, pid):
self.pid = pid
def set_parent(self, parent):
self.ppid = parent
def set_arrive_time(self, arrive_time):
self.arrive_time = arrive_time
def set_need_time(self, need_time):
self.need_time = need_time
class Pnode(object): def init(self): self.node = Pcb() self.child = []
def set_node_pid(self, pid):
self.node.set_pid(pid)
def set_node_parent(self, ppid):
self.node.set_parent(ppid)
def set_node_arrtime(self, arrtime):
self.node.set_arrive_time(arrtime)
def set_node_needtime(self, needtime):
self.node.set_need_time(needtime)
def get_node_pid(self):
return self.node.pid
def get_node_parent(self):
return self.node.ppid
def get_node_arrtime(self):
return self.node.arrive_time
def get_node_needtime(self):
return self.node.need_time
class WaitList(object): def init(self): self.waitlist = {} self.starttime = 0 def addtolist(self, pid, arrtime, needtime): l = self.waitlist if pid in l: print "process already exists" else: l[arrtime] = Pnode() l[arrtime].set_node_pid(pid) l[arrtime].set_node_arrtime(arrtime) l[arrtime].set_node_needtime(needtime)
def show(self):
l = self.waitlist
print "pid \t\t arrive time \t\t start time"
for p in l:
if (p > self.starttime):
self.starttime += p-self.starttime
print l[p].get_node_pid(),":\t\t",l[p].get_node_arrtime(),"\t\t",self.starttime
self.starttime += l[p].get_node_needtime()
def main(): waitlist = WaitList() print "please input process number" n = input() for i in xrange(n): pid,arrtime,needtime = map(int,raw_input("please input process id,arrive time,need time").split()) waitlist.addtolist(pid, arrtime, needtime) waitlist.show()
if name == "main": main()