Assignment 2 Solution

Description



As a data scientist working at the CMPE Airlines, it is your job to always try new ideas in order to increase the e ciency. After working at the CMPE Airlines for a long time you realize that the passengers are really annoyed by the long waiting times for luggage hand-in and security checks. Some of the passengers are even missing their ights because of the long waiting times at the queues. You come up with a few ideas to reduce these waiting times, but before proposing your ideas to the management board you decide to actually test your design ’in silico’ if the new proposals will work or not on the data you have.




In the current system there is a rst come rst serve queue before the L luggage hand-in counters. Whenever there is a free counter , rst person in the queue goes to the free counter and gives their luggage. After handing in luggage, they go into a second queue for a security check. This is also a rst come rst serve queue and there are S security counters. Similarly, whenever a security counter is free, rst person in the queue goes to that counter for the security check. This is visualized in the Figure 1.









Figure 1: Initial queue structure




Changes To Implement



You have 3 di erent ideas to make these queues more e cient. You need to simulate the system and collect data for 8 possible scenarios where you implement each of these 3 ideas or not. The rst data you need to collect is the average time between the arrival of a passenger to the terminal and her departure from the security check. Second data you need to collect is the number of passengers who are late to their ights.




Instead of making the queues rst come, rst serve you can make them rst-to- y, rst serve. The person who is ight is earliest will move to the rst place of the line. This applies to both luggage hand-in queue and security queue. You are hoping that this would reduce the number of people who are late to their ights.



CMPE Airlines has a special VIP Passenger program. Each passenger is either in this program or not. As a rm you are trusting these customers. You decide that you can make these VIP passengers skip the security queue entirely. You are hoping that this would have an impact on other people’s waiting time as well since VIP passengers won’t keep the security counters busy.



As some people do not have a luggage to hand-in, you can implement an online ticketing system. As a result the people who does not carry a luggage can skip the rst queue entirely and go in line for the security


check immediately. You are hoping that this would have an impact on other people’s waiting time as well, since passengers without a luggage won’t keep the luggage hand-in counters busy.




You are asked to simulate and collect the statistics for each of the 8 cases in the order given by this table.






First-to-Fly
No Security
Using Online


First Serve
Check for VIP
Ticketing








Case 1:
é
é
é








Case 2:
Ë
é
é








Case 3:
é
Ë
é








Case 4:
Ë
Ë
é








Case 5:
é
é
Ë








Case 6:
Ë
é
Ë








Case 7:
é
Ë
Ë








Case 8:
Ë
Ë
Ë














Input/Output Format



For this project, time will be measured in minutes. Start of the day will be at 0 minutes. All of the given times in the input will be integers, indicating how many minutes from the start of the day. Output is also in minutes. As a result, you do not need to perform time conversions in your code.




3.1 Input Format




The rst line of the input le holds 3 integers, P , L and S, number of passengers, number of check-in counters and number of security gates.




In the following P lines, the passenger data is given, one passenger per line. Each line holds 4 integers and 2 characters, the time at which the passenger will arrive at the airport, the time at which the passenger has to board her ight, the time it will take for her to hand in her luggage, the time her security control will take and the VIP membership and luggage state of that passenger. If the passenger is a VIP member the rst character will be a ’V’, otherwise it will be a ’N’. Similarly, if the passenger has a luggage to hand in, the second character will be a ’L’, otherwise it will be a ’N’.


3.2 Output Format




Your program should calculate and print out the two statistics for each case given in the table in eight separate lines.




Average waiting time for passengers.




Number of passengers who get out of the procedure after their boarding time.




3.3 Example Input




8
2 2




1
10 6
3
N L
3
16 3
6
N N
4
11 2
3
V N
5
15 2
5
N N
6
921VN



16191
1
N L
17263
5
N L
18221
3
N L



There are 8 passengers, 2 luggage counters and 2 security counters.




The 1st passenger comes to the terminal at 1 minutes. Her ight is at 10 minutes, she will spend 6 minutes on the luggage counter and she will spend 3 minutes on the security counter. She is not a VIP passenger and she has a luggage (She has to go to the luggage counter even if online ticketing is implemented.).




The 5th passenger comes to the terminal at 6 minutes. Her ight is at 9 minutes, she will spend 2 minutes on the luggage counter and she will spend 1 minutes on the security counter. She is a VIP passenger and has no luggage. As a result, if online ticketing is implemented she will skip the luggage counters and go straight into the security queue. If both online ticketing and no security check for VIP passengers is implemented she will directly board on her ight, waiting for 0 minutes in the procedure.


3.4 Example Output




7.625 3




7.375 3




6.25 1




6.125 0




5.75 2




5.5 1




4.5 1




4.5 1




8 lines for each separate simulation cases.




As an example, compare lines 3 and 4. These are the cases where VIP security skip is implemented. These lines di er by the queuing rules. You can see that making the queues rst-to- y, rst serve we are ef-fectively reducing the average waiting time and preventing a passenger from being late to their ight. You can see a similar trend on lines 5 and 6, where online ticketing is implemented.




If you compare the lines 4 and 8, you can also see that implementing all the options can cause more people to miss their ights. This happens because the passengers 2 and 4 skip the luggage queue and ll both security counters. They end up blocking passenger 1 from proceeding with the security check and cause her to miss her ight.







Grading



Grading of this project is based on the success of your code in test cases. Your score will be the sum of collected points from each test case. Each test case will have equal weight. Maximum score is 100.




For each test case total points will be divided to 8 equal parts for each of the simulation cases. You can still get a partial score by successfully implementing a subset of these 8 simulation cases. If you decide to do this, make sure that you print "0 0" for the cases you did not calculate.





Implementation Details



Variable limits are as follows:



1 P 5,000




1 L;S 20




1 All the times given in minutes 50,000




Execution time limit is 1 seconds. If your code runs more than 1 seconds on a test case you will get 0 points from that test case.






Even if a passenger is already late to their ight they will still stay in the queues. Do not put people out of the procedure based on this.



You can safely assume that no two passengers will arrive at the terminal at the same time or leave luggage counters at the same time.



If two di erent events, say a passenger leaving a luggage counter and another passenger leaving a security counter, is happening at the same time, the person leaving the luggage counter can occupy the security counter that was emptied by the other passenger in that instant. Same thing applies for a passenger arriving at the terminal and another pas-senger leaving a luggage counter at the same time. Hint: You can ensure this by making sure that you simulate simultaneous events in this order:



A passenger leaving a security counter.



A passenger leaving a luggage counter.



A passenger arriving at the terminal.



Your program will be compiled with cmake CMakeLists.txt && make command and executed with ./project2 inputFile output-File command.






Warnings



Make sure an executable is created after executing cmake CMake-Lists.txt && make commands. Otherwise, no executable will be created and your code will fail in grading.









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