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)

function main(input) {
  var inputArr = input.split(/\r?\n/).map(inp => inp.split(" "));
  var ranking = inputArr[1].map(vote => parseInt(vote)).sort().reverse();
  var m = inputArr[0][1]
  var idx = m - 1;
  var popular = ranking[idx];
  var totalVotes = ranking.reduce((total, vote) => total + vote);
  
 for(var i = 0; i < m; i++) {
 	if( ranking[i] < 1.0 * totalVotes / m * 4 ) {
    	return false;
    }   
 }
  return true;
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));