If we use a hash table, there must be a slot/bucket that has at least a keys assigned to it, where a is the load factor of the current hash table. True False A binary search tree of n nodes may have a depth/height as large as 2(n). False True If A[1.n] is sorted, we can find the k th smallest element in A[1...n] in O(1) time. True False

If we use a hash table, there must be a slot/bucket that has at least a keys assigned to it, where a is the load factor of the current hash table. True False A binary search tree of n nodes may have a depth/height as large as 2(n). False True If A[1.n] is sorted, we can find the k th smallest element in A[1...n] in O(1) time. True False

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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Similar questions

A hash-map has been constructed with quadratic-hashing. The hashing function is h(k;) = (3 * k; + 7) mod 17 and the table length is N = 17. How many cells will be probed by the call of insert(2) 1 4 5 6 7 8 10 11 12 13 14 15 16 26 89 11 35 70 59 Note: First row contains the indices and the second row contains the items.
We have n elements {x1, ..., xn} we want to hash into a table T of size s = 2n. Let us consider the following method of hashing these n elements into T: For each i = 1,..., n, do the following: 1. Pick a permutation of [1,..., s] uniformly at random. Call this permutation T; : [s] → [s], which maps each index to the element which ends up in that index. 2. Set j : : 1. 3. While T[T;(j)] has an element in it, increment j. 4. Place x; in T[T;(j)]. 1.1 Show that while inserting any ;, the probability that there are at least t iterations of the while loop in Step 3 is at most 2-t.
We create a Hash-table of integers where the hash function returns the first digit of the integer(For example, for 33 it returns 3). If we use a binary search tree as the value storage of our hash-table, what is the time-complexity to look up an integer in it?* O(Log(N)) O(N*Log(N)) O(N) O(N^2)
What is the worst-case performance of a lookup operation in a hashmap and why? Group of answer choices A- O(1), hashmap always has a constant time lookup, and that is why we like using this associative data structure. B- O(lg(n)) hashmap has a log(n) lookup because we are able to perform a binary search on the keys because our hashmap always maintains a sorted order of entries added. C- O(n) because we can have a bad hash function that puts all of our items in the same bucket, thus we would have to iterate through all n items.
Linear Probing uses an auxilliary hash function that searches an array for the next empty space to insert a key if the original hash function mapped to an index that already had a key. True False Quadratic probing is meant to resolve a problem that linear probing suffers from, that problem is: O Linear probing tends to create long clusters of full cells making subsequent linear probes take longer and longer. Linear probing tends to overwrite key values after a second probe. Linear probing requires a linked list. O Linear probìng calculations require O(n*lg{n}} time. Collisions are a design problem of the hash table data structure that causes the hash insertion and deletion functions to run O(n^2) time. O True O False
Given a hash table of size 9 with hash function x%9. Write the element order of the linear probe hash table when these keys are inserted in the given order. 1,20,11,28,25,9,18 Answer is just a sequence of elements in the same format. Use hypen - to indicate empty space. For example a table like below must be written as in the following: 11 28 9,28,-,11,1,-,- Cevap: Kalan Süre 1:37:31
L is a list of data items that is linear. Implement the list as: I an ordered list; (ii) a linear open addressed hash table using a suitable hash function of your choosing.Use binary search or hashing to find a collection of keys on representations I and ii), respectively. Compare how well the two approaches performed over list L.
Generate 11 unique random elements and perform the extendible hashing. The bucket size is three (3) and the Hash function is the following: H(X) => Suppose the global depth is X. Then the Hash Functi9on returns X LSBs. Make sure that in every hashing step there is an equivalent explanation.
2-A linear probing hash table of length 10 uses the hash function h(x) = x mod 10 + 1. mod is the reminder opertatro. For example the h(42) = 42 mod 10 + 1 = 2 + 1 = 3 so we insert 42 in t he position 3 in the array. After inserting 6 integer keys into an initially empty hash table, the array of keys is 1 2 3 4 5 7 8 9. 42 23 34 52 46 33 a- insert the key 35 b- insert the key 12 c- insert the key 10
For the operation below, provide the worst case running time in terms of n (Big O notation). Briefly justify your answer >>> Using binary search in a sorted singly linked list (as you completed in LAB 4). The implementation for __len__ traverses the list to count each node
A frequently used hash family is the matrix multiplication hash family that we have introduced in class. Suppose we have n buckets {1, 2, ..., n}, we will use a binary string of length b = log₂ n to index each bucket. (For example, if we have 4 buckets, they will be indexed as 00, 01, 10, 11.) Now, we would like to hash a u-bit binary string x into the hash table (For example, x could be an 8-bit string 10100110). To hash this u-bit string x into a bucket, we use the hash function hд(x) = (Ax)mod 2, where A is a b x u dimensional binary matrix, and x is a u × 1 dimensional column vector. As a result, h(x) will be a b × 1 dimensional vector which shows the bucket index that x will be hashed to. (For example, x is an 8-bit string [10100110]™, and A is a [1 0 1 1 0 0 0 then h₁(x) ) = (Ax)mod 2 = 2 × 8 dimensional matrix [ 0 1 1 0 1 0 1 [1, 0], which means that x will be hashed to bucket 2.) Prove that the above hash function h₁(x) = (Ax)mod 2 is a universal hash family. [Hint: Consider…
A linear probing hash table of length 10 uses the hash function h(x) = x mod 10 + 1. mod is the reminder operator. For example the h(42) = 42 mod 10 + 1 = 2 + 1 = 3 so we insert 42 in the position 3 in the array. After inserting 6 integer keys into an initially empty hash table, the array of keys is…