硬貨における強制通用力の上限

legalTender.scala

object legalTender extends App {
    val yenCoins = List(1
                    ,5
                    ,10
                    ,50
                    ,100
                    ,500)
    val yenMax = 20
    
    def sumCoins(coins: List[Int], max: Int): Int = coins.map(_ * max).sum
    
    println(sumCoins(yenCoins, yenMax))
}