Rock

package Random

import kotlin.random.Random

val choices = listOf("rock", "paper", "scissors")
val winningCases = arrayOf(listOf("rock", "scissors"), listOf("paper", "rock"), listOf("scissors", "paper"))

fun main() {
    println("Rock, Scissors or Paper?")
    val userChoice = userChoice()
    val compChoice = compChoice()
    result(userChoice, compChoice)
}

fun compChoice(): String {
    val randIndex = Random.nextInt(0, 3)
    return choices[randIndex]
}

fun userChoice(): String? {
    return readLine()?.toLowerCase()
}

fun result(userChoice: String?, compChoice: String) {
    print("I chose $compChoice, you chose $userChoice. ")
    val case = listOf(userChoice, compChoice)
    when(case) {
        in winningCases -> println("You won:'(")
        else -> if(userChoice != compChoice) println("You lost!") else println("Draw!")
    }
}