gahfy

class CheckBox(){
    var isChecked: Boolean = false

    fun click(){
        isChecked = !isChecked
    }
}

class TextView(private var text: String){
    fun click(){

gahfy

fun main(){
    val mementoManager = LongMementoManager()
    println("Start")
    println("Fibonacci at rank 1000 is: ${fibonacci(1000, mementoManager)}")
}

gahfy

fun fibonacci(rank: Int, mementoManager: LongMementoManager): Long{
    val result =  when(rank){
        0 -> 0L
        1 -> 1L
        else -> {
          val rankMinus1 = fibonacci(rank-1, mementoManager)
          val rankMinus2 = mementoManager.getMemento(rank-2)?.restore()?:0L
          rankMinus1 + rankMinus2
        }
    }

gahfy

class LongMementoManager{
    private val mementos = hashMapOf<Int, LongMemento>()

    fun saveMemento(index: Int, memento: LongMemento){
        mementos[index] = memento
    }

    fun getMemento(index: Int): LongMemento?{
        return mementos[index]
    }

gahfy

class LongMemento{
    private var numberToSave: Long = 0L

    fun save(number: Long): LongMemento{
        numberToSave = number
        return this
    }

    fun restore(): Long = numberToSave
}

gahfy

fun fibonacci(rank: Int): Long{
    return when(rank){
        0 -> 0L
        1 -> 1L
        else -> fibonacci(rank-1).toLong() + fibonacci(rank-2).toLong()
    }
}

fun main(){
    println("Start")

gahfy

class Calculator{
    private var result = 0
    private var currentOperation = "0"

    fun addNumber(number: Int){
        result += number
        currentOperation = "$currentOperation + $number"
    }

    fun getResult() = result

gahfy

fun main(){
    val thai = RadioButton("Are you thai?")
    thai.radioButtonMediator = RadioButtonMediator { checked ->
        if(checked){
            println("ผมพูดภาษาไทยได้ครับ")
        }
        else{
            println("I can speak english.")
        }
    }

gahfy

class RadioButton(private val label: String){
    var isChecked: Boolean = false
    var radioButtonMediator: RadioButtonMediator? = null

    fun click(){
        isChecked = !isChecked
        radioButtonMediator?.notify(isChecked)
    }
}

gahfy

fun interface RadioButtonMediator{
    fun notify(checked: Boolean)
}