릿코드 380. Insert Delete GetRandom O(1) 코틀린

그냥 o(1)으로 동작하는 셋을 구현하라는문제
해시셋쓰면될듯

정답

class RandomizedSet() {
    val randomHashSet = hashSetOf<Int>()


    fun insert(`val`: Int): Boolean {
        if (randomHashSet.contains(`val`)){
            return false
        }else{
            randomHashSet.add(`val`)
            return true
        }
    }

    fun remove(`val`: Int): Boolean {
        if (randomHashSet.contains(`val`)){
            randomHashSet.remove(`val`)
            return true
        }else{
            return false
        }
    }

    fun getRandom(): Int {
        return randomHashSet.random()
    }

}