Problem:
Score : 200 points

Problem Statement

We have held a popularity poll for N items on sale. Item i received A_i votes.

From these N items, we will select M as popular items. However, we cannot select an item with less than \dfrac{1}{4M} of the total number of votes.

If M popular items can be selected, print Yes; otherwise, print No.

Constraints

1 \leq M \leq N \leq 100

1 \leq A_i \leq 1000

A_i are distinct.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N M
A_1 ... A_N

Output

If M popular items can be selected, print Yes; otherwise, print No.

Sample Input 1

4 1
5 4 2 1

Sample Output 1

Yes

There were 12 votes in total. The most popular item received 5 votes, and we can select it.

Sample Input 2

3 2
380 19 1

Sample Output 2

No

There were 400 votes in total. The second and third most popular items received less than \dfrac{1}{4\times 2} of the total number of votes, so we cannot select them. Thus, we cannot select two popular items.

Sample Input 3

12 3
4 56 78 901 2 345 67 890 123 45 6 789

Sample Output 3

Yes

Solution in Kotlin (1.0.0) (judge verdict: Accepted)

fun main(args: Array<String>) {
    val (N, M) = listOfInt()
    val A = listOfDouble().sortedDescending()
    val total = A.sum()
    val limit = 1.0 / M.toDouble() / 4.0
    var good = A.subList(0, M).all { (it / total) >= limit }
    val ans = if (good) "Yes" else "No"
    println(ans)
}


fun next() = readLine()!!
fun nextInt(delta: Int = 0) = Integer.parseInt(next()) + delta
fun nextLong() = next().toLong()
fun nextDouble() = next().toDouble()
fun listOfString() = next().split(" ")
fun listOfInt() = listOfString().map(String::toInt)
fun listOfLong() = listOfString().map(String::toLong)
fun listOfDouble() = listOfString().map(String::toDouble)
fun listOfInt(delta: Int = 0) = listOfString().map { Integer.parseInt(it) + delta }
fun listOfInt(vararg offset: Int) = listOfString().map { Integer.parseInt(it) }.mapIndexed { index, int -> int + offset[index % offset.size] }
fun listOfLong(delta: Long = 0L) = listOfString().map { java.lang.Long.parseLong(it) + delta }
fun listOfLong(vararg offset: Long) = listOfString().map { java.lang.Long.parseLong(it) }.mapIndexed { index, long -> long + offset[index % offset.size] }
fun listOfDouble(delta: Double = 0.0) = listOfString().map { java.lang.Double.parseDouble(it) + delta }
fun pairIntLong() = listOfLong().let { Pair(it[0].toInt(), it[1]) }
fun tripleIntIntLong() = listOfLong().let { Triple(it[0].toInt(), it[1].toInt(), it[2]) }
fun tripleIntLongLong() = listOfLong().let { Triple(it[0].toInt(), it[1], it[2]) }
fun pairIntLong(offset: Pair<Int, Long> = Pair(0, 0L)) = listOfLong().let { Pair(it[0].toInt() + offset.first, it[1] + offset.second) }
fun tripleIntIntLong(offset: Triple<Int, Int, Long> = Triple(0, 0, 0L)) = listOfLong().let { Triple(it[0].toInt() + offset.first, it[1].toInt() + offset.second, it[2] + offset.third) }
fun tripleIntLongLong(offset: Triple<Int, Long, Long> = Triple(0, 0L, 0L)) = listOfLong().let { Triple(it[0].toInt() + offset.first, it[1] + offset.second, it[2] + offset.third) }