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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;


public class Main {
    private static int MOD = 1000000007;


    public static void main(String[] args) throws IOException {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        String str = br.readLine();
        String[] split = str.split(" ");
        int n = Integer.parseInt(split[0]);
        int m = Integer.parseInt(split[1]);

        split = br.readLine().split(" ");

        int total = 0;

        List<Integer> hyous = new ArrayList<>();
        for (String s : split) {
            int hyou = Integer.parseInt(s);
            total += hyou;
            hyous.add(hyou);
        }

        hyous.sort(Collections.reverseOrder());

        int ikichi = total / (4 * m);
        int amari = total % (4 * m);
        if(amari != 0) {
            ikichi++;
        }
        for (int i = 0; i < m; i++) {
            int hyou = hyous.get(i);
            if (hyou < ikichi) {
                System.out.println("No");
                return;
            }
        }

        System.out.println("Yes");

    }
}