How to Remove Duplicates in an Array in Kotlin


How to Remove Duplicates in an Array in Kotlin ?

Answer

To remove duplicates in an array in Kotlin, you can use the distinct or toSet methods.



✐ Examples

1 Remove Duplicates using distinct Method

In this example,

  1. We create an array named arrayWithDuplicates with duplicate elements.
  2. We use the distinct method on arrayWithDuplicates to remove duplicates.
  3. The distinct method returns a list with only unique elements.
  4. Finally, we convert the list back to an array using the toTypedArray method and print it to standard output.

Kotlin Program

fun main(args: Array<String>) {
    val arrayWithDuplicates = arrayOf(1, 2, 3, 4, 1, 2, 5, 6, 7, 3)
    val arrayWithoutDuplicates = arrayWithDuplicates.distinct().toTypedArray()
    println("Array without duplicates: ${arrayWithoutDuplicates.joinToString()}")
}

Output

Array without duplicates: 1, 2, 3, 4, 5, 6, 7

2 Remove Duplicates using toSet Method

In this example,

  1. We create an array named arrayWithDuplicates with duplicate elements.
  2. We use the toSet method on arrayWithDuplicates to convert it to a set, which automatically removes duplicates.
  3. The toSet method returns a set with only unique elements.
  4. Finally, we convert the set back to an array using the toTypedArray method and print it to standard output.

Kotlin Program

fun main(args: Array<String>) {
    val arrayWithDuplicates = arrayOf(1, 2, 3, 4, 1, 2, 5, 6, 7, 3)
    val arrayWithoutDuplicates = arrayWithDuplicates.toSet().toTypedArray()
    println("Array without duplicates: ${arrayWithoutDuplicates.joinToString()}")
}

Output

Array without duplicates: 1, 2, 3, 4, 5, 6, 7

Summary

In this tutorial, we learned How to Remove Duplicates in an Array in Kotlin language with well detailed examples.




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