Kotlin - Collections

Collections are a common concept for most programming languages. A collection usually contains a number of objects of the same type and Objects in a collection are called elements or items.
The Kotlin Standard Library provides a comprehensive set of tools for managing collections. The following collection types are relevant for Kotlin:
Kotlin List  -  List is an ordered collection with access to elements by indices. Elements can occur more than once in a list.
Kotlin List  -  List is an ordered collection with access to elements by indices. Elements can occur more than once in a list.
Kotlin Set  -   Set is a collection of unique elements which means a group of objects without repetitions.
Kotlin Set  -   Set is a collection of unique elements which means a group of objects without repetitions.
Kotlin Map -  Map (or dictionary) is a set of key-value pairs. Keys are unique, and each of them maps to exactly one value.
Kotlin Map -  Map (or dictionary) is a set of key-value pairs. Keys are unique, and each of them maps to exactly one value.
Kotlin  provides the following types of collection:
Collection or Immutable Collection
Collection or Immutable Collection
Mutable Collection
Mutable Collection
Immutable Collection or simply calling a Collection interface provides read-only methods which means once a collection is created, we can not change it because there is no method available to change the object created.
fun main() {
    val numbers = listOf("one", "two", "three", "four")
    
    println(numbers)
}

When you run the above Kotlin program, it will generate the following output:
[one, two, three, four]

Mutable collections provides both read and write methods.
fun main() {
    val numbers = mutableListOf("one", "two", "three", "four")
    
    numbers.add("five")
    
    println(numbers)
}

When you run the above Kotlin program, it will generate the following output:
[one, two, three, four, five]

Q 1 - Which of the following is true about Kotlin Collections?
A - Kotlin provides mutable and immutable collection
B - List, Set and Map are Kotlin Collections
C - Kotlin Map can store values in Key-Value pairs
D - All of the above
All the given statements are true about Kotlin Collections
Q 2 - What will be the output of the following program:
fun main() {
    val numbers = listOf("one", "two", "three", "four")
    
    numbers = listOf("five")
}

A - This will print 0
B - This will raise just a warning
C - Compilation will stop with error
D - None of the above
This will stop with error: val cannot be reassigned.
Q 2 - Which statement is not correct?
A - Kotlin List can have duplicate values
B - Kotlin Set can not have duplicate values
C - Immutable collection does not provide methods to change/update the collection.
D - Kotlin does not provide collection types: sets, lists, and maps
Kotlin provides collection types: sets, lists, and maps

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