fun main(args: Array<String>){
	val num = readLine()!!.toInt()
    val list = readLine()!!.split(" ").map { it.toInt() }.sorted()
    
	val center = num / 2
	if (num % 2 == 0) {
		println((list.get(center - 1).toFloat() + list.get(center).toFloat()) / 2)
	} else {
		println(list.get(center).toFloat())
	}
}