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 Fortran (gfortran v4.8.4) (judge verdict: Accepted)

program main
    implicit none
    integer n,m
    integer, allocatable, dimension(:) :: a
    integer i,sum, d, count
    read(*,*) n,m
    allocate(a(n))
    read(*,*) a

    sum = 0
    count = 0
    do i = 1,n
        sum = sum + a(i)
    end do

    d = sum/(4*m)

    if (mod(sum, 4*m) == 0) then
        d = d-1
    end if

    do i = 1,n
        if(a(i) > d) then
            count = count + 1
        end if
    end do

    if(count >= m) then
        write(*,*) "Yes"
    else
        write(*,*) "No"
    end if

end program