TCS NQT Hashing Quiz-1

Answer :: (B)

EXPLANATION :

A hash function is any function that can be used to map data of arbitrary size to fixed-size values. The values returned by a hash function are called hash values, hash codes, digests, or simply hashes. The values are used to index a fixed-size table called a hash table. Use of a hash function to index a hash table is called hashing or scatter storage addressing.

 

Answer :: (D)

EXPLANATION :

A hash table is used to implement associative arrays which has a key-value pair, so the hash table maps keys to values.

Direct addressing is possible only when we can afford to allocate an array that has one position for every possible key.

Answer :: (B)

EXPLANATION :

Making the hash function random is not really a good choice, although it is considered one of the techniques to avoid collisions along with Separate chaining and Simple Uniform Hashing.

Making the hash function random is not really a good choice, although it is considered one of the techniques to avoid collisions along with chaining and simple uniform hashing. Chaining is the best

Answer :: (B)

EXPLANATION ::

When several elements compete for the same bucket in the hash table it is called Collision.

Since every key has a unique array position, searching takes a constant time

When more than one element are competing for the same bucket in the hash table, this condition is known as the Collision.

In simple uniform hashing, any given element is equally likely to hash into any of the slots available in the array.

In simple chaining, the load factor is the average number of elements stored in a chain and is given by the ratio of a number of elements stored to the number of slots in the array.