Difference between List and Array types in Kotlin

List and array are two popular collections supported by Kotlin. By definition, both these collections allocate sequential memory location. In this article, we will take an example to demonstrate the difference between these two types of collections.

Example

In the following example, we will see how we can declare an array and a List in Kotlin and how we can manipulate the values of the same.

fun main(args: Array<String>) {

   val a = arrayOf(1, 2, 3)

   // Printing all the values of array a
   println("The Array contains:")
   a.forEach{
      println(it)
   }


   val names = listOf("stud1", "stud2", "stud3")

   // Printing all the values of list names
   println("
The List contains: ")
   names.forEach {
      println(it)
   }


   var days: MutableList<String> = mutableListOf(
      "Monday", "Tuesday", "Wednesday",
      "Thursday", "Friday", "Saturday", "Sunday"
   )

   // Printing all the values of MutableList list
   println("
Given Mutable List contains:")
   days.forEach{
      print(it)
   }

   println("

Mutable List after modification:")
   days.forEach{
      print(it + ", ")
   }

}

Output

It will generate the following output −

The Array contains:
1
2
3

The List contains:
stud1
stud2
stud3

Given Mutable List contains:
MondayTuesdayWednesdayThursdayFridaySaturdaySunday

Mutable List after modification:
Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday,