Question

What is modulo and how is it used in a hashing function? Explain and give an example.

What is a collision in a hash table? Name and explain at least two ways in which a collision can be handled. Give examples.

Answer 1

What is modulo and how is it used in a hashing function? Explain and give an example.

Modulo in hash function can be defines as mod

The Equation can be given as h(k) = k mod N

Where k = hash code(integer) which is generated from the key.

N = number of buckets.

Example: h(k) = k mod 4

  

Key	Element
0	45
1	67
2	78
3	12

What is a collision in a hash table? Name and explain at least two ways in which a collision can be handled. Give examples.

Collision in hash table:

If the Hash Function is mapped to two keys which are different in same table or if a key which is inserted newly is mapped to occupied slot in this two cases collision occurs.

Handling Collision:

(1).Collision can be avoided by selecting Hash function Properly.

(2).Collision can be handles by Open Addressing and Seperate chaining method.

Example:

Using seeprate chaining