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 JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

"use strict"
function main(arg) {
    var m = arg.trim().split("\n")[0].split(' ').map(Number)[1]
    var ai = arg.trim().split("\n")[1].split(' ').map(Number).sort((a,b) => b - a)
    var sum = 0
    var sum_m = 0
    for (var i = m - 1; i < ai.length; i++) {
        sum_m += ai[i]
    }
    for (var i = 0; i < ai.length; i++) {
        sum += ai[i]
    }
    // console.log(sum)
    if (sum_m * (4 * m) < sum ) {
        console.log('No')
    } else {
        console.log('Yes')
    }
    
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));