Kevmo.kt

import kotlin.math.PI

// declarations

interface ThingWithMass {
    fun weightInKilograms(): Double
}

// create a class
open class Animal(var age: Int)

class Cat(age: Int) : Animal(age), ThingWithMass {
    override fun weightInKilograms(): Double = 2.0 * age
}

class Dog(age: Int) : Animal(age)


// declare what a glass is
class Glass(var height: Double, var diameter: Double, var fullness: Double) : ThingWithMass {
    override fun weightInKilograms(): Double = computeVolume() / 1000

    fun computeVolume() = (diameter / 2) * (diameter / 2) * PI * height
}


fun kevmoMain() {
    Cat(3)

    val kitty = Cat(5)

    var myGlass = Glass(3.5, 4.0, .3)
    println("volume of the glass is ${myGlass.computeVolume()}")


    val yourglass = Glass(6.0, 12.0, 0.7)
    println("your glass contains ${yourglass.computeVolume()} milliliters")


    val totalWeight = kitty.weightInKilograms() + myGlass.weightInKilograms() + yourglass.weightInKilograms()
    println("The weightInKilograms of our cats and glasses is: ${totalWeight}")
}