Hash tables-java coding | Computer Science

 Assignment Description: The goal of this assignment is to work with hash functions and understand the performance of the Division method using open addressing techniques discussed in the slides. Page 2 Write one simple program that uses a fixed set of 50 unique keys stored in an array as follows (Important: hard-code the array content in your program and make sure you have same exact key values below in the same order): int[] keys = {1234, 8234, 7867, 1009, 5438, 4312, 3420, 9487, 5418, 5299,  5078, 8239, 1208, 5098, 5195, 5329, 4543, 3344, 7698, 5412,  5567, 5672, 7934, 1254, 6091, 8732, 3095, 1975, 3843, 5589,  5439, 8907, 4097, 3096, 4310, 5298, 9156, 3895, 6673, 7871,  5787, 9289, 4553, 7822, 8755, 3398, 6774, 8289, 7665, 5523}; The program allows the user to select a hash function, from the menu, to be invoked on the set of keys. Keep it simple as follows: —–MAIN MENU—– 0 – Exit Program 1 – Run HF1 (Division with Linear Probing) 2 – Run HF2 (Division with Quadratic Probing) 3 – Run HF3 (Division with Double Hashing) 4 – Run HF4 (Student-Designed Function) The hash functions are defined below. To keep the implementation simple, design the hash table (call it Table) (of size 50) as a 2D array (50 rows and 2 columns) (int[][] Table = new int[50][2];) The first column stores the keys while the second column stores number of probes used to resolve collisions. After calling the hash function from the menu, the output of the program should display the hash table followed by the sum of all probe values in the table. Declare a separate method in your class, say sumProbes(), to perform this calculation and return the sum of all probes in the table (second column of the table). Note that the total number of probes a hashing function generates indicates the performance level of the function – The smaller the sum of probes the better the hash function. HF1: Declare a separate method HF1() that implements the Division method discussed in the slides with Linear Probing for collision resolution. HF2: Declare a separate method HF2() that implements the Division method discussed in the slides with Quadratic Probing for collision resolution. HF3: Declare a separate method HF3() that implements the Division method discussed in the slides with Double Hashing for collision resolution. For the second hashing function, use the following function and increment (see example in slides)  H2 (key) = 30 – key % 25;  Increment is (key % 50) + j * H2 (key) for j=1, 2, 3, 4, … Note: It is possible that HF3 will not be able to determine and empty index in the hash table for a give key, especially when very few empty entries remain in the hash table. I this care and to avoid entering into an infinite loop, limit number of attempt to locate a key in the hash table to no more than 50 tries. In such case, printout a message like this example: “Unable to has key 43654 to the table”. Page 3 Note this phenomenon happen due to not applying Load Factoring to our table. HF4: Declare a separate method HF4() that implements a hash function of your own design. The sky is your limit. You can come up with your own hash function or take and improve one of the above three functions by either using a different hashing method (other than Division method) or a different collision resolution method. Aim to come up with a function that beats the above three function (i.e., your function generates smallest number of probes for the given set of keys). Note: See the note in HF3 and apply it to you HF4 if necessary. The assignment is very specific and it must be implemented as specified. Any deviation from these requirements is not acceptable and receives no points. No exceptions. Only complete and correct code receives credit. Code must compile and run on its own as received. Using code from outside sources receives NO credit. Format the output following the sample run below. Sample output for format illustration purpose only (Our table is of size 50 elements) Hash table resulted from HF2: Index Key probes ————————  0 4576 0  1 9876 2  2 2341 0  3 8722 3  4 9988 4  5 1111 0  6 3443 1  7 4444 0  8 7788 1  9 2321 0 ———————— Sum of probe values = 11 probes. 

Place your order
(550 words)

Approximate price: $22

Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
The price is based on these factors:
Academic level
Number of pages
Basic features
  • Free title page and bibliography
  • Unlimited revisions
  • Plagiarism-free guarantee
  • Money-back guarantee
  • 24/7 support
On-demand options
  • Writer’s samples
  • Part-by-part delivery
  • Overnight delivery
  • Copies of used sources
  • Expert Proofreading
Paper format
  • 275 words per page
  • 12 pt Arial/Times New Roman
  • Double line spacing
  • Any citation style (APA, MLA, Chicago/Turabian, Harvard)

Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

Read more

Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

Read more

Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.

Read more

Privacy policy

Your email is safe, as we store it according to international data protection rules. Your bank details are secure, as we use only reliable payment systems.

Read more

Fair-cooperation guarantee

By sending us your money, you buy the service we provide. Check out our terms and conditions if you prefer business talks to be laid out in official language.

Read more