Python多線程經典問題之乘客做公交車算法實例

2019-11-25 16:17:53

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本文實例講述了Python多線程經典問題之乘客做公交車算法。分享給大家供大家參考，具體如下：

問題描述：

乘客乘坐公交車問題，司機，乘客，售票員協同工作,通過多線程模擬三者的工作。
司機：開車，停車
售票員：打開車門，關閉車門
乘客：上車，下車

用Python的Event做線程同步通信，代碼如下：

# *-* coding:gb2312 *-*import threadingimport timestationName=("車站0","車站1","車站2","車站3","車站4","車站5","車站6")currentStationIndex = -1eventBusStop = threading.Event()eventClosedDoor = threading.Event()eventOpenedDoor = threading.Event()stationCount = len(stationName)class Passenger(threading.Thread):  def __init__(self,no,getonStation,getoffStation):    self.no =no    self.getonStation=getonStation    self.getoffStation=getoffStation    threading.Thread.__init__(self)  def run(self):    bExit= False    global currentStationIndex    global stationCount    bAlreadyGetOnStation = False    while not bExit:      eventOpenedDoor.wait()      if self.getonStation == currentStationIndex and bAlreadyGetOnStation == False:        print "乘客%d在%s上車" %(self.no,stationName[currentStationIndex])        bAlreadyGetOnStation =True      elif self.getoffStation == currentStationIndex:        print "乘客%d在%s下車" %(self.no,stationName[currentStationIndex])        bExit = True      time.sleep(1)class Driver(threading.Thread):  def run(self):    bExit= False    global currentStationIndex    global stationCount    while not bExit:      print "司機: 公交車開始行駛....."      time.sleep(5)      currentStationIndex += 1      print "司機: 到站 ",stationName[currentStationIndex]      eventBusStop.set()      eventClosedDoor.wait()      eventClosedDoor.clear()      if currentStationIndex == stationCount-1:        bExit= Trueclass Conductor(threading.Thread):  def run(self):    bExit= False    global currentStationIndex    global stationCount    while not bExit:      eventBusStop.wait()      eventBusStop.clear()      print "售票員打開車門：%s到了" %(stationName[currentStationIndex])      eventOpenedDoor.set()      time.sleep(5)      print "售票員關閉車門"      eventOpenedDoor.clear()      eventClosedDoor.set()      if currentStationIndex == stationCount-1:        bExit = Truedef test():  passPool=[]  passPool.append(Passenger(0,0,3))  passPool.append(Passenger(1,1,3))  passPool.append(Passenger(2,2,4))  passPool.append(Passenger(3,0,5))  passPool.append(Passenger(4,1,3))  passPool.append(Passenger(5,2,4))  passPool.append(Passenger(6,4,5))  passPool.append(Passenger(7,0,2))  passPool.append(Passenger(8,1,3))  passPool.append(Conductor())  passPool.append(Driver())  leng = len(passPool)  for i in range(leng):    passPool[i].start()if __name__=='__main__':  test()

輸出結果如下：