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In this tutorial, we will write a Program to implement the Heap Sort algorithm in Kotlin programming language.

Heap sort is a comparison-based sorting technique based on the Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. We repeat the same process for the remaining elements.

Heap Sort Algorithm in Kotlin

Let's write the Kotlin program to implement the Heap sort algorithm to sort an array of elements in ascending order:

import java.util.*

fun <E: Comparable<E>> Array<E>.sort() {
    val middle = size / 2 - 1
    for (i in middle downTo 0) {
        heapify(this, size, i)
    }
    for (i in size - 1 downTo 0) {
        this[0] = this[i].also { this[i] = this[0] }
        heapify(this, i, 0)
    }
}

private fun <E: Comparable<E>> heapify(arr: Array<E>, heapSize: Int, root: Int) {
    var largest = root
    val leftNode = 2 * root + 1
    val rightNode = 2 * root + 2
    if (leftNode < heapSize && arr[leftNode] > arr[largest]) largest = leftNode
    if (rightNode < heapSize && arr[rightNode] > arr[largest]) largest = rightNode

    if (largest != root) {
        arr[root] = arr[largest].also { arr[largest] = arr[root] }
        heapify(arr, heapSize, largest)
    }
}

fun main(args: Array<String>) {
    val nums = arrayOf(2, 12, 89, 23, 76, 43, 12)
    nums.sort()
    println(Arrays.toString(nums))

    val languages = arrayOf("Kotlin", "Java", "C#", "R", "Python", "Scala", "Groovy", "C", "C++")
    languages.sort()
    println(Arrays.toString(languages))
}

Output:

[2, 12, 12, 23, 43, 76, 89]
[C, C#, C++, Groovy, Java, Kotlin, Python, R, Scala]

Related Data Structures and Algorithms in Kotlin

1. Bubble Sort Algorithm in Kotlin
2. Heap Sort Algorithm in Kotlin
3. Insertion Sort Algorithm in Kotlin
4. Merge Sort Algorithm in Kotlin
5. Quick Sort Algorithm in Kotlin
6. Selection Sort Algorithm in Kotlin
7. Stack Data Structure Implementation in Kotlin
   
8. Queue Data Structure Implementation in Kotlin
   
9. Deque Implementation in Kotlin
   
10. Singly Linked List Implementation in Kotlin
    
11. Doubly Linked List Implementation in Kotlin
    
12. Circular Linked List Implementation in Kotlin