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 C (GCC 5.4.1) (judge verdict: Accepted)

#include <stdio.h>
#include <math.h>

int main (void) {
    int all;
    int pickup;
    
    scanf("%d %d", &all, &pickup);

    int value[all];
    int all_value = 0;

    for (int i = 0; i < all; i++) {
        scanf("%d", &value[i]);
        all_value += value[i];
    }

    float judge = (float)all_value / (4 * pickup);
    int cnt = 0;

    for (int i = 0; i < all; i++) {
        //printf("value:%d, judge:%f\n", value[i], judge);
        if (judge <= value[i]) {
            cnt++;
        }
    }
    if (cnt >= pickup) {
        printf("Yes\n");
    } else {
        printf("No\n");
    }

    return 0;
}