Hands-On Object-Oriented Programming with Kotlin

The hashCode() function

In mathematics, a set is a collection of unique values that does not allow duplicates. The hashCode is a function that generates a unique number for each input.

Let's take a look at the importance of the hashCode function:

1. Create three objects of a Person class, two with the same values and one with a different value:

class Person(var name : String, var age: Int, var height: Double)val p1 = Person("Abid", 40, 6.0)val p2 = Person("Abid", 40, 6.0)val p3 = Person("Khan", 40, 6.0)

2. Create a hash set of the Person class and add all three objects in it:

val set = hashSetOf(p1,p2,p3) 

3. Check the size of this collection. The set must remove the duplicates and keep only unique elements. In this case, the size of this set ...