import math
import random

#---------------QUESTION 1A---------------
def nextTime(mean):
    for i in range(mean):
        x=random.random()
        arrivaltime = (-(mean)) * (math.log(1-x))
        print arrivaltime


#---------------------------------------------------------------------------------------------------------------------------------------------------------------------
#---------------QUESTION 1B---------------

def singlequeue():

    #Initialising the variables used for calculating the average
    totalqueue=0
    count=0

    #Asking the user what they wish to use for alpha and beta
    a = raw_input('Please enter the average interarrival time (alpha): ')
    b = raw_input('Please enter the average service times (beta): ')

    #Setting alpha and beta to integer numbers
    a =int(a)
    b=int(b)

    #For 1 -> n times, do
    for i in range(1, 201):

        c=0                                 #c to store the current time
        ta=0                                #ta to store the time to the next customer arrival
        ts=0                                #ts to store the time until the customer has finished being served
        q=1                                 #Q to store the current length of the queue
        maxqueue=0                          #maxqueue is used to show the maximum queue after the 8 hours


        while c < 480:                      #While the time is less than 8 hours
            if q!=0:                        #If the length of the queue is not 0

                if ta<ts:
                    ts = ts - ta
                    c = c + ta
                    q=q+1
                    x=random.random()
                    ta = -a * (math.log(1-x))

                    if maxqueue < q:
                        maxqueue = q

                else:
                    ta = ta - ts
                    c = c + ts
                    q=q-1
                    x=random.random()
                    ts = -b * (math.log(1-x))


            elif q==0:                      #If the length of the queue is 0
                c = c +ta
                q=q+1
                x=random.random()
                ta = -a * (math.log(1-x))

                if maxqueue < q:
                    maxqueue = q


        if totalqueue == 0:                 #If totalqueue equals 0, then the total queue is the maximum length
            totalqueue = maxqueue
        else:                               #If a totalqueue has already been set, then the maximum queue is simply added to the total
            totalqueue = totalqueue + maxqueue

        count += 1                          #Counting how many times the simulation is run

    avgqueue = totalqueue / float(count)    #Working out that the average length is the totalqueue divided by the amount of times the simulation is run

    print 'Average queue was : ', avgqueue  #Printing the value of the Average Queue Length