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 Common Lisp (SBCL 2.0.3) (judge verdict: Wrong Answer)

(defun app ()
    (let* ((n (read))
        (m (read))
        (a (make-array n :initial-element 0))
        (sum 0)
        (ans "Yes"))
        (dotimes (i n)
            (setf (aref a i) (read))
            (incf sum (aref a i))
        )
        (sort a '>)

        (dotimes (i m)
        (if (<= (aref a i) (/ sum (* 4 m)))
            (setq ans "No")
        )
        )
    (format t "~A~%" ans)
    )
)

(app)