排队论的C实现

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以下鄙人实现了排队论思想，语言是C语言

 

#include<stdio.h>

#include<float.h>

 

int main()

{

 

/************************************what we know in the system**************************************/

    float arrivals[] = {0.4, 1.6, 2.1, 3.8, 4.0, 5.6, 5.8, 7.2};//the time of each customer's arrival

    float departures[] = {2.4, 3.1, 3.3, 4.9, 8.6};//the time of each customer's departure

    int acount = 0;//the index of arrivals array

    int dcount = 0;//the index of departures array

/***************the clock and clock event in the simulating system******************/

    float clock = 0;//simulation clock

    float clock_event[2] = {arrivals[acount],departures[dcount]};//clock[0] means arrival time,clock[1] means departure time

    int clock_event_times[2] = {0, 0}; //clock_event_times[0] means the count of arrival event happened;

                                        //clock_event_times[1] means the count of departure event happened

/*****************system state ****************************/

    int serve_status = 0;//false means ideal and 1 means busy

    int no_in_queue = 0;//the number in queue

    float time_of_arrival[4] = {0};//the time of arrival

    float time_of_last_event = 0;// the time of last event

 

/*****************statistical counters***************/

    int no_delayed = 0;//the number of delayed

    float total_delay = 0;//the total delay time

    float area_under_Q = 0;//the area under queue(t)

    float area_under_B = 0;//the area under busy(t)

    

/********the stop time***/

    char temp;

    int end_event;

    printf("Please input the stop event of this simulating system(a means arrival and d means departure): ");

    scanf("%c", &temp);

    if (temp == 'd')

        end_event = 1;

    else

        end_event = 0;

    int ordinal;

    printf("Please input the customer's ordinal of the stop event you have input:");

    scanf("%d", &ordinal);

    

/***********start********************/

    while(clock_event_times[end_event] < ordinal)

    {

 

        if(clock_event[0]<clock_event[1] )//arrival event

        {

            clock = clock_event[0];

            acount += 1;

            clock_event[0] = arrivals[acount];

            clock_event_times[0] += 1;

            if(serve_status == 0)//no body

            {

                serve_status = 1;

            }

            else

            {

                time_of_arrival[no_in_queue] = clock;

                area_under_B += serve_status * (clock - time_of_last_event);

                area_under_Q += no_in_queue * (clock - time_of_last_event);

                no_in_queue += 1;

            }

 

        }

        else//department event

        {

            clock = clock_event[1];

            dcount += 1;

            clock_event[1] = departures[dcount];

            clock_event_times[1] += 1;

            area_under_B += clock - time_of_last_event;

            if(no_in_queue == 0)

            {

                serve_status = 0;

            }

            else

            {

                clock_event[1] = departures[dcount];

                total_delay += clock - time_of_arrival[0];

                area_under_Q += no_in_queue * (clock - time_of_last_event);

                no_in_queue -= 1;

                time_of_arrival[0] = time_of_arrival[1];

                time_of_arrival[1] = time_of_arrival[2];

                time_of_arrival[2] = time_of_arrival[3];

 

            }

 

        }

        time_of_last_event = clock;

    }

    printf("Number delayed: %d\n", clock_event_times[1]);

    printf("Total delay: %2f\n", total_delay);

    printf("Area under Q(t): %2f\n", area_under_Q);

    printf("Area under B(t): %2f\n", area_under_B);

 

    return 0;

}