---

typealias Operation = (Double, Double) -> Double


fun calculate(
    a: Double,
    b: Double,
    operation: Operation
): Double {

    return operation(a,b)
}


fun main() {


    val operations = mapOf<String, Operation>(

        "+" to { a,b -> a+b },

        "-" to { a,b -> a-b },

        "*" to { a,b -> a*b },

        "/" to { a,b ->
            if(b == 0.0)
                Double.NaN
            else
                a/b
        },

        "%" to { a,b -> a%b },

        "^" to { a,b ->
            Math.pow(a,b)
        },

        "max" to { a,b ->
            maxOf(a,b)
        }
    )


    print("Введите первое число: ")
    val a = readln().toDouble()


    print("Введите операцию: ")
    val symbol = readln()


    print("Введите второе число: ")
    val b = readln().toDouble()


    val operation = operations[symbol]


    if(operation != null){

        val result = calculate(a,b,operation)

        println("Ответ: $result")

    } else {

        println("Такой операции нет")
    }

}