Solution to minimum swaps 2 on hackerrank

minimumSwaps2.kt

// Complete the minimumSwaps function below.
fun minimumSwaps(arr: Array<Int>): Int {
    var numberOfSwaps = 0
    val sortingMap: HashMap<Int, Int> = HashMap()

    // Build hashing map, ex.
    // [7, 1, 3, 2, 4, 5, 6]
    // [0, 1, 2, 3, 4, 5, 6]
    for (hashingIndex in 0 until arr.size) {
        sortingMap[arr[hashingIndex]] = hashingIndex
    }

    for (loopingIndex in 0 until arr.size) {
        if (loopingIndex + 1 != arr[loopingIndex]) {
            val temp = arr[loopingIndex]
            arr[loopingIndex] = loopingIndex + 1
            arr[sortingMap[loopingIndex + 1]!!] = temp

            sortingMap[temp] = sortingMap[loopingIndex + 1]!!
            sortingMap[loopingIndex + 1] = loopingIndex

            numberOfSwaps++
        }
    }

    return numberOfSwaps
}