Kotlin Integer Binary Search

binarySearch.kt

fun binarySearch(numbers: List<Int>, number: Int): Int {
    var leftIndex = 0
    var rightIndex = numbers.size - 1

    while(leftIndex <= rightIndex) {
        val midIndex = (leftIndex + rightIndex) / 2
        val midNumber = numbers[midIndex];

        when {
            midNumber == number -> return midIndex
            midNumber < number -> leftIndex = midIndex + 1
            else -> rightIndex = midIndex - 1
        }
    }

    return -1
}