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How to sort a HashSet in Kotlin

How to sort a HashSet in Kotlin.

Here's a step-by-step tutorial on how to sort a HashSet in Kotlin:

Step 1: Create a HashSet​

First, let's start by creating a HashSet in Kotlin. A HashSet is an unordered collection of elements, so we need to sort it manually.

val set = HashSet<Int>()
set.add(5)
set.add(3)
set.add(7)
set.add(1)

In this example, we've created a HashSet of integers and added four elements to it.

Step 2: Convert HashSet to a List​

To sort the elements in the HashSet, we need to convert it to a List. Kotlin provides a convenient way to convert a collection to a list using the toList() function.

val list = set.toList()

Now, list contains the elements from the HashSet.

Step 3: Sort the List​

Next, we can sort the list using the sorted() function. The sorted() function returns a new list with the elements sorted in ascending order.

val sortedList = list.sorted()

Here, sortedList contains the elements from the list in sorted order.

Step 4: Convert Sorted List Back to HashSet​

After sorting the list, we can convert it back to a HashSet using the toHashSet() function.

val sortedSet = sortedList.toHashSet()

Now, sortedSet is a sorted HashSet with the elements in ascending order.

Step 5: Print the Sorted HashSet​

Finally, let's print the elements of the sorted HashSet to verify that it's sorted.

for (element in sortedSet) {
    println(element)
}

This will print the elements of the sorted HashSet in ascending order.

Complete Example: Here's the complete example that demonstrates how to sort a HashSet in Kotlin:

fun main() {
    val set = HashSet<Int>()
    set.add(5)
    set.add(3)
    set.add(7)
    set.add(1)

    val list = set.toList()
    val sortedList = list.sorted()
    val sortedSet = sortedList.toHashSet()

    for (element in sortedSet) {
        println(element)
    }
}

Output: The output of the above code will be:

1
3
5
7

Conclusion: In this tutorial, you learned how to sort a HashSet in Kotlin. By converting the HashSet to a List, sorting the list, and converting it back to a HashSet, you can achieve the desired result.