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: Accepted)

"use strict";
function main(input) {
  let kari = input[0].trim().split(" ").map(i => parseInt(i));
  const n = kari[0];
  const m = kari[1];
  let a = input[1].trim().split(" ").map(i => parseInt(i));

  a.sort(function(a, b) {
    return b - a;
  });

  let sum = 0;
  for(let i=0;i<n;i++){
    sum += a[i];
  }

  let judge = false;
  for(let i=0;i<m;i++){
    if((sum/(4*m)) > a[i]){
      judge = true;
    }
  }

  console.log(judge?"No":"Yes");
}
main(require('fs').readFileSync('/dev/stdin', 'utf8').trim().split("\n"));