// @EXPECTED_RESULTS@: TIME_LIMIT_EXCEEDED, WRONG_ANSWER
import kotlin.math.ceil

fun main() {
    val (_, f) = readln().split(" ").map { it.toDouble() }
    val values = readln().split(" ").map { it.toDouble() }
    if (values.size == 1) {
        return println(findBestFps(f, values.first()))
    }
    val div = 1_000_000.0
    var best = Double.MAX_VALUE
   for (i in div.toLong() .. (f.toLong()*div.toLong() )) {
       val current = values.calulateBest(i/div)
       if(current< best) {
           best = current
       }
   }
    println(best)
}

fun findBestFps(end: Double, values: Double, start: Double = 1.0): Double {
    var step = (end - start) / 2
    var current = start + step
    if (current < start) current = start
    var best = values.calulateBest(current)
    step /= 2
    while (step > 2 * EPSILON) {
        val left = values.calulateBest(current - step)
        val right = values.calulateBest(current + step)
        best = best.coerceAtMost(left).coerceAtMost(right)
        when (best) {
            left -> current -= step
            right -> current += step
        }
//        println("$step: $best ( $current)")
        step /= 2
    }
    return best
}

const val SPEED = 1000
const val EPSILON = 1e-18

fun List<Double>.calulateBest(currentFramerate: Double) = sumOf { it.calulateBest(currentFramerate) }

fun Double.calulateBest(currentFramerate: Double): Double {
    val timeNeeded = this / SPEED
    val frameDuration = 1 / currentFramerate
    val test = ceil(timeNeeded / frameDuration)
    if (test * frameDuration - timeNeeded <= EPSILON) {
        return timeNeeded
    } else {
        return (test) * frameDuration
    }
}