Set in Scala | Set-2

Prerequisite: Set in Scala | Set-1Adding items in Mutable SetIn Set, We can only add new elements in mutable set. +=, ++== and add() method is used to add new elements when we are working with mutable set in mutable collection and += is used to add new elements when we are working with mutable set in immutable collection. Example 1: 

Output:

Set before addition of new elements:
Set(for, G, Geek)

Set after addition of new elements:
Set(geek23, for, Geeks, G, Geek, Geeks12, geeksForgeeks100, GeeksforGeeks)

  Example 2: 

Output:

Set before addition of new elements:
Set(G, Geek, for)

Set after addition of new elements:
Set(for, Geek, G, geeks1000, GeeksforGeeks)

 Removing elements from the Mutable setIn Set, We can only remove elements in the mutable set. -= and --= methods are used to delete elements and we can also use retain(), clear(), and remove() methods to delete elements when we are working with mutable set in the mutable collection. -= operator is used to delete elements when we are working with mutable set in immutable collection. Example 1: 

Output:

Set before deletion:
Set(300, 100, 800, 500, 600, 400)

Set after deletion:
Set(800, 500, 400)

  Example 2: 

Output:

Set before deletion:
Set(300, 100, 800, 500, 600, 400)
Set(66, 55, 11, 44, 77)

Set after using retain() method:
Set(800, 600)

Set after using clear() method:
Set()

 Adding items in immutable SetIn immutable set, We cannot add elements, but we can use + and ++ operators to add element from the immutable set and store the result into a new variable. Here, + is used to add single or multiple elements and ++ is used to add multiple elements defined in another sequence and in concatenation of immutable set. Example: 

Output:

Set before addition:
Set(500, 600, 800, 300, 400, 100)
Set(77, 44, 66, 11, 55)

Set after addition:
Set(500, 900, 600, 800, 300, 400, 100)
Set(500, 600, 800, 300, 400, 200, 100)
Set(500, 700, 1000, 600, 800, 300, 400, 100)
Set(500, 77, 44, 66, 600, 11, 55, 800, 300, 400, 100)

Removing elements from the immutable setIn immutable set, We cannot remove elements, but we can use - and -- operators to remove elements from the immutable set and store the result into a new variable. Here, - operator is used to remove one or more elements and -- operator is used to remove multiple elements defined in another sequence. Example: 

Output:

Set before deletion:
Set(500, 900, 700, 600, 800, 300, 400, 100)

Set after deletion:
Set(500, 900, 700, 600, 800, 300, 400)
Set(500, 900, 700, 600, 800, 100)
Set(900, 600, 800, 300, 400, 100)

 Set OperationsNow we will see some of the basic mathematical operations on the Set like Union, Intersection, and Difference.

1. Union: In this, we could simply add one Set with other. Since the Set will itself not allow any duplicate entries, we need not take care of the common values. To perform union, we use union() method.
2. Intersection: To get the common values from both Sets we use intersect() method. It returns a new set which contains all the common values present in both sets.
3. Difference: To get the difference of two Sets we use diff() method. It returns the set which contains all the that are not present in myset2.

Example: 

Output:

Intersection:
Set(77, 22, 44, 66, 55)

Difference:
Set(33, 11, 111)

Union:
Set(88, 33, 77, 22, 44, 66, 11, 99, 55, 111)