) Multiple answers: Multiple answers are accepted for this question ct one or more answers and submit. For keyboard navigation. SHOW MORE V A hash function takes a key and produces an index into the hash table. The next step in this process is often something like 'h%SIZE' so that the hash value of the key will fit within the table (having SIZE elements, you see). Common techniques involve exclusive or of bits within the key and folding different sections of bits within the key into each other. The best hash method for character strings is to simply add up the ASCII values of their individual characters. Coming up with a perfect hash for a given set of keys can be a difficult and time-consuming task.

) Multiple answers: Multiple answers are accepted for this question ct one or more answers and submit. For keyboard navigation. SHOW MORE V A hash function takes a key and produces an index into the hash table. The next step in this process is often something like 'h%SIZE' so that the hash value of the key will fit within the table (having SIZE elements, you see). Common techniques involve exclusive or of bits within the key and folding different sections of bits within the key into each other. The best hash method for character strings is to simply add up the ASCII values of their individual characters. Coming up with a perfect hash for a given set of keys can be a difficult and time-consuming task.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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In this task, two hash tables should should be implemented. You can follow the followinginstructions:- In class HashTable implement a hash table and consider the following:(i) Keys are integers (therefore also negative!) and should be stored in the tableint[] data.(ii) As a hash function take h(x) = (x · 701) mod 2000. The size of the table istherefore 2000. Be careful when computing the index of a negative key. Forexample, the index of the key x = −10 ish(−10) = (−7010) mod 2000 = (2000(−4) + 990) mod 2000 = 990.Hence, indices should be non-negative integers between 0 and 1999!(iii) Implement insert, which takes an integer and inserts it into a table. Themethod returns true, if the insertion is successful. If an element is already inthe table, the function insert should return false.(iv) Implement search, which takes an integer and finds it in the table. The methodreturns true, if the search is successful and false otherwise.(v) Implement delete, which takes an integer and deletes it…
Add to LinearProbingHashST a delete()method that deletes a key-value pair by setting the value to null (but not removingthe key) and later removing the pair from the table in resize(). Your primary challenge is to decide when to call resize(). Note : You should overwrite the null value ifa subsequent put() operation associates a new value with the key. Make sure that yourprogram takes into account the number of such tombstone items, as well as the numberof empty positions, in making the decision whether to expand or contract the table
- In class HashTable implement a hash table and consider the following:(i) Keys are integers (therefore also negative!) and should be stored in the tableint[] data.(ii) As a hash function take h(x) = (x · 701) mod 2000. The size of the table istherefore 2000. Be careful when computing the index of a negative key. Forexample, the index of the key x = −10 ish(−10) = (−7010) mod 2000 = (2000(−4) + 990) mod 2000 = 990.Hence, indices should be non-negative integers between 0 and 1999!(iii) Implement insert, which takes an integer and inserts it into a table. Themethod returns true, if the insertion is successful. If an element is already inthe table, the function insert should return false.(iv) Implement search, which takes an integer and finds it in the table. The methodreturns true, if the search is successful and false otherwise.(v) Implement delete, which takes an integer and deletes it form the table. Themethod returns true, if the deletion is successful and false otherwise.(vi)…
#5. Please give a program to implement hashcode and equals..
g. Add to LinearProbingHashST a delete()method that deletes a key-value pair by setting the value to null (but not removingthe key) and later removing the pair from the table in resize(). Your primary challenge is to decide when to call resize(). Note : You should overwrite the null value ifa subsequent put() operation associates a new value with the key. Make sure that yourprogram takes into account the number of such tombstone items, as well as the numberof empty positions, in making the decision whether to expand or contract the table.
We may utilise two methods without implementing them: countand unambiguous The DictionaryEntry object's count is returned via the Count method. whereas Clear removes all DictionaryEntry from the inner hash tableitems from the internal hash tableWrite a program that utilizes these methods:
I need help with this question, please. Parts A and B A.) Add the following numbers to an 11-entry hash table using linear probing to resolve collisions. Stop before adding an item that would result in α > 0.75. This means you might not use all the numbers. (Spoiler alert: you won't use them all.) 39 68 60 71 83 52 99 55 49 77 58 26 76 66 37 28 For the hash function, simply take the number mod the table size. In 11 blanks, write the number that would end up at that entry in the table. If there is no number at that location, write empty. B.) Add the following numbers to a 23-entry hash table using linear probing to resolve collisions. Stop before adding an item that would result in α > 0.75. This means you may not use all the numbers. 39 68 60 71 83 52 99 55 49 77 58 26 76 66 37 28 For the hash function, simply take the number mod the table size. In 23 blanks, write the number that would end up at that entry in the table. If there is no number at that location, write…
Given the following Java functions, transcribe it into a Python 3 program. /*** Add a new entry with the specified key, value and hash code to* the specified bucket. It is the responsibility of this* method to resize the table if appropriate.*/void addEntry(int hash, Object key, Object value, int bucketIndex) {table[bucketIndex] = new Entry(hash, key, value, table[bucketIndex]);if (size++ >= threshold)resize(2 * table.length);}
Excute the Program about Hash and show me the result . Source code import java.util.*; import java.io.*; class HashTable { public static void main(String[] args) throws IOException { int key; try { BufferedReader in = new BufferedReader (new InputStreamReader(System.in)); System.out.print ("How many elements you want to enter to the hash table : "); int n = Integer.parseInt(in.readLine()); Hashtable hashTable = new Hashtable(); for(int i = 0; i < n; i++) { System.out.print("Enter key for the hash table : "); key = Integer.parseInt(in.readLine()); System.out.print("Enter value for the key : "); hashTable.put(key, in.readLine()); } Map map = new TreeMap(hashTable); System.out.println(map); } catch(NumberFormatException ne) { System.out.println(ne.getMessage() + " is not a legal value."); System.out.println("Please enter a numeric value."); System.exit(1); } } }//End
2. Write a program by implementing your own PRNG (e.g., using a hash function). You must not use any existing random class or function but implement your own. Produce random bytes (like above). Note the purpose of this part is not to design a strong PRNG that passes randomness tests, but rather for comparison with an existing strong PRNG (above).
The hash code for Strings can be calculated once, at the time the String is created, which could potentially reduce its complexity.The precomputed value would be returned by subsequent calls to hashCode. This has the potential to be promising because a String's value never changes. How would you rate the effectiveness of such a procedure?
Given the following Java functions, transcribe it into a Python 3 program. /*** Rehashes the contents of this hash table into a new array with a* larger capacity. This method is called automatically when the* number of keys in this hash table reaches its threshold.*/void resize(int newCapacity) {Entry[ ] oldTable = table;int oldCapacity = oldTable.length;if (oldCapacity == MAXIMUM_CAPACITY) {threshold = Integer.MAX_VALUE;return threshold;} Entry[ ] newTable = new Entry[newCapacity];transfer(newTable);table = newTable;threshold = (int)(newCapacity * loadFactor);}