42889.kt

class Solution {
    fun solution(N: Int, stages: IntArray): IntArray {

        var stageCountMap = mutableMapOf<Int, Int>()

        var failRateMap = mutableMapOf<Int, Float>()

        var remained = stages.size

        for (stage in stages){

            if (stageCountMap.keys.contains(stage)){
                val value = stageCountMap[stage]
                stageCountMap[stage] = (value!! + 1)
            }else{
                stageCountMap[stage] = 1
            }
        }

        for (stage in 1 .. N){

            val count = stageCountMap[stage] ?: 0

            var failRate: Float = (count.toFloat() / remained)

            failRateMap[stage] = failRate

            remained -= count
        }

        return failRateMap.toList().sortedByDescending { (key, value) -> value }.asSequence().map { it.first }.toList().toIntArray()
    }
}