```import Gender.* data class Hero(val name: Stri...

# codereview

[amit]

import Gender.*

data class Hero(val name: String, val age: Int, val gender: Gender?)

enum class Gender {
    MALE, FEMALE
}

fun main() {
    val heroes = listOf(
        Hero("The Captain", 60, MALE),
        Hero("Frenchy", 42, MALE),
        Hero("The Kid", 9, null),
        Hero("Lady Lauren", 29, FEMALE),
        Hero("First Mate", 29, MALE),
        Hero("Sir Stephen", 37, MALE))


    val mapByName = heroes.associateBy { it.name }

    val unknownHero = Hero("Unknown", 0, null)

    val age1= mapByName.getOrElse("unknown") { 0 }

    println("$age1")
}