What is a Set in Java Collections?

A Set is a collection in Java that:

--> Does not allow duplicate elements

--> Does not guarantee index (no ordering like List)

--> Stores only unique values

It is part of java.util.Set interface.

Main Types of Set

1. HashSet

--> No order maintained

--> Fast performance

--> Allows one null

Example

import java.util.* ;

public class HashSetExample { public static void main ( String [] args ) { Set < String > set = new HashSet <>();

set . add ( "Apple" ); set . add ( "Banana" ); set . add ( "Apple" ); // duplicate ignored set . add ( "Mango" );

System . out . println ( set ); } } output: [ Apple , Banana , Mango ]

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2. LinkedHashSet

--> Maintains insertion order

--> No duplicates allowed

Example

import java.util.* ;

public class LinkedHashSetExample { public static void main ( String [] args ) { Set < Integer > set = new LinkedHashSet <>();

set . add ( 10 ); set . add ( 30 ); set . add ( 20 ); set .…