fun main(args: Array<String>){
    val age = readLine()!!.toInt()

    when(age){
        1 -> { ageIsOne() }
        2 -> { ageIsTwo() }
        else -> throw
    IllegalArgumentException("1歳か2歳のみ許容します")
    }
    
}

fun ageIsOne(){
    println("Hello World")
}

fun ageIsTwo(){
    val num1 = readLine()!!.toInt()
    val num2 = readLine()!!.toInt()
    println(num1 + num2)
}