Kotlin Trie Delete Optimized

trieOptimizedDelete.kt

override fun delete(key: String) {
    delete(key, 0, root)
}

private fun delete(key: String, index: Int, node: Node<Value>) {
    if (index == key.length)
        node.value = null
    else node.children[key[index]]?.run {
        delete(key, index + 1, this)
        if (children.isEmpty() && value == null) node.children.remove(key[index])
    }
}