cambio de divisas

fun convertir(valor: Double, from: String, to: String): Double{
    val euroAReal = 4.5
    val euroAPeso = 25.0
    val pesoAReal = 0.18
    val euroAEs = 125.0
    return when(from){
        "euro" -> when(to){
            "euro" -> valor
            "real" -> valor * euroAReal
            "peso" -> valor * euroAPeso
            "es" -> valor * euroAEs
            else -> 0.0
        }
        "real" -> when(to){
            "euro" -> valor / euroAReal
            "real" -> valor
            "peso" -> valor / pesoAReal
            "es" -> valor / euroAReal * euroAEs
            else -> 0.0
        }
        "peso" -> when(to){
            "euro" -> valor / euroAPeso
            "real" -> valor * pesoAReal
            "peso" ->