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 PHP7 (7.0.15) (judge verdict: Accepted)

<?php
// Your code here!
$insert1 = explode(" ",trim(fgets(STDIN)));
$N = $insert1[0];
$M = $insert1[1];
$insert2 = explode(" ",trim(fgets(STDIN)));

$sum = array_sum($insert2);
for($i=0; $i <= count($insert2)-1; $i++){
    if($insert2[$i] >= $sum / (4*$M)){
        $results[] = $insert2[$i];
    }
}

if(count($results) >= $M){
    echo "Yes".PHP_EOL;
}else{
    echo "No".PHP_EOL;
}