// mall.c -- use the Queue interface
// compile with queue.c
#include <stdio.h>
#include <stdlib.h> // for rand() and srand()
#include <time.h> // for time()
#include "queue.h" // change Item typedef
#define MIN_PER_HR 60.0
bool newcustomer(double x); // is there a new customer?
Item customertime(long when); // set customer parameters
int main(void)
{
Queue line,line1;
Item temp; // new customer data
int hours; // hours of simulation
int perhour; // average # of arrivals per hour
long cycle, cyclelimit; // loop counter, limit
long turnaways = 0; // turned away by full queue
long customers = 0; // joined the queue
long served = 0,served1 = 0; // served during the simulation
long sum_line = 0,sum_line1 = 0; // cumulative line length
int wait_time = 0,wait_time1 = 0; // time until Sigmund is free
double min_per_cust; // average time between arrivals
long line_wait = 0,line_wait1 = 0; // cumulative time in line
InitializeQueue(&line);
InitializeQueue(&line1);
srand((unsigned int) time(0)); // random initializing of rand()
puts("Case Study: Sigmund Lander's Advice Booth");
puts("Enter the number of simulation hours:");
scanf("%d", &hours);
cyclelimit = MIN_PER_HR * hours;
puts("Enter the average number of customers per hour:");
scanf("%d", &perhour);
min_per_cust = MIN_PER_HR / perhour;
for (cycle = 0; cycle < cyclelimit; cycle++)
{
if (newcustomer(min_per_cust))
{
if (QueueIsFull(&line)&&QueueIsFull(&line1))
turnaways++;
else
{
customers++;
temp = customertime(cycle);
if (QueueItemCount(&line) < QueueItemCount(&line1))
EnQueue(temp, &line);
else
EnQueue(temp, &line1);
}
}
if (wait_time <= 0 && !QueueIsEmpty(&line))
{
DeQueue (&temp, &line);
wait_time = temp.processtime;
line_wait += cycle - temp.arrive;
served++;
}
if (wait_time1 <= 0 && !QueueIsEmpty(&line1))
{
DeQueue (&temp, &line1);
wait_time1 = temp.processtime;
line_wait1 += cycle - temp.arrive;
served1++;
}
if (wait_time > 0)
wait_time--;
if (wait_time1 > 0)
wait_time1--;
sum_line += QueueItemCount(&line);
sum_line1 += QueueItemCount(&line1);
}
if (customers > 0)
{
printf("customers accepted: %ld\n", customers);
printf(" turnaways: %ld\n", turnaways);
printf(" line:\n");
printf(" customers served: %ld\n", served);
printf("average queue size: %.2f\n",(double) sum_line / cyclelimit);
printf(" average wait time: %.2f minutes\n",(double) line_wait / served);
printf(" line1:\n");
printf(" customers served1: %ld\n", served1);
printf("average queue1 size: %.2f\n",(double) sum_line1 / cyclelimit);
printf(" average wait time1: %.2f minutes\n",(double) line_wait1 / served1);
}
else
puts("No customers!");
EmptyTheQueue(&line);
puts("Bye!");
return 0;
}
// x = average time, in minutes, between customers
// return value is true if customer shows up this minute
bool newcustomer(double x)
{
if (rand() * x / RAND_MAX < 1)
return true;
else
return false;
}
// when is the time at which the customer arrives
// function returns an Item structure with the arrival time
// set to when and the processing time set to a random value
// in the range 1 - 3
Item customertime(long when)
{
Item cust;
cust.processtime = rand() % 3 + 1;
cust.arrive = when;
return cust;
}