Hashing and Hash Tables

What is the purpose of hashing in computer science?

• To transform a string of characters into a shorter length value

• To illustrate the concept of data structures

• To distribute keys in an array using a hash function

• To store and retrieve keys in a rapid manner

What is a hash table used for?

• To illustrate the concept of data structures

• To handle collisions in hashing

• To index and retrieve items in a database

• To store the original string

Which method of hashing involves adding up ASCII values of all the characters in the string and taking modulo of a table size?

• Digit Extraction

• Mid-square

• Folding

• Division

What is the purpose of linear probing in handling collisions?

• To store each string in a chain (linked list)

• To search the next empty slot and put the string there

• To divide the string/identifier by using the modulus operator

• To extract the middle part of the bit representation of the square of a key

What is the search complexity of linear probing if there are many collisions?

• O(n^2)

• O(n)

• O(1)

• O(log n)

What is the purpose of chaining in handling collisions?

• To store each string in a chain (linked list)

• To divide the string/identifier by using the modulus operator

• To search the next empty slot and put the string there

• To extract the middle part of the bit representation of the square of a key

What is the purpose of the Folding method in hashing?

• To divide the key value into a number of parts

• To add up ASCII values of all the characters in the string and take modulo of a table size

• To use any hash method and then perform rotation to get a new hash address

• To extract a predefined digit of the given number as the hash address

What is the purpose of the Division method in hashing?

• To divide the string/identifier by using the modulus operator

• To extract a predefined digit of the given number as the hash address

• To add up ASCII values of all the characters in the string and take modulo of a table size

• To use any hash method and then perform rotation to get a new hash address

What is the purpose of the Mid-square method in hashing?

• To square the string/identifier and then use an appropriate number of bits from the middle of the square to obtain the hash-key

• To extract a predefined digit of the given number as the hash address

• To use any hash method and then perform rotation to get a new hash address

• To divide the key value into a number of parts