Hash Functions in Computer Science

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What is the primary goal of a well-designed hash function?

To minimize the number of collisions
To distribute items uniformly throughout the table (correct)
To maximize the number of collisions
To sort items in a specific order

What is the purpose of increasing the table capacity in a hash table implementation?

To make the hash table more efficient
To increase the number of collisions
To reduce collisions (correct)
To make the hash table more complex

In the division method of hash function design, what type of number is a good choice for the value of m?

A non-prime number close to an exact power of 2
A non-prime number not close to an exact power of 2
A prime number close to an exact power of 2
A prime number not close to an exact power of 2 (correct)

What is the primary clustering problem in a hash table implementation?

Items are not distributed uniformly throughout the table (A) Signup and view all the answers

What is the purpose of the multiplication method of hash function design?

To distribute items uniformly throughout the table (A) Signup and view all the answers

What is the primary advantage of using universal hashing in hash function design?

It provides a random distribution of items (D) Signup and view all the answers

What is the key idea behind hash tables?

The size of the table does not depend on the size of the universe of keys (D) Signup and view all the answers

What is the main disadvantage of direct-access tables?

Effect of huge universe of keys (A) Signup and view all the answers

What is the purpose of a hash function?

To map the key to a location (B) Signup and view all the answers

What is the result of a many-to-one mapping in hash tables?

Many collisions (C) Signup and view all the answers

What is the average time complexity of a hash table with perfect hashing?

O(1) (C) Signup and view all the answers

What is the purpose of handling collisions in hash tables?

To avoid collisions (C) Signup and view all the answers

What is the main advantage of hash tables over direct-access tables?

Efficient handling of huge universes of keys (A) Signup and view all the answers

What is the time complexity of direct-address-insert operation?

O(1) (A) Signup and view all the answers

What is the primary drawback of linear probing?

Primary clustering (A) Signup and view all the answers

What is the purpose of the second hash function in double hashing?

To increase random probing (C) Signup and view all the answers

What is the characteristic of the probe sequence in quadratic probing?

It is a quadratic sequence of the hash table indices (B) Signup and view all the answers

What is the effect of secondary clustering on hash table performance?

It degrades the performance of the hash table (C) Signup and view all the answers

What is the advantage of using double hashing over linear probing?

It sharply reduces clustering (A) Signup and view all the answers

What is the primary advantage of using quadratic probing over linear probing?

It avoids primary clustering (C) Signup and view all the answers

What is the purpose of the load factor in chained hashing?

To determine the average case running time (B) Signup and view all the answers

What is the characteristic of the probe sequence in open-addressing schemes?

It is a permutation of the hash table indices (A) Signup and view all the answers