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: Wrong Answer)

#include<stdio.h>
int main(void){
  int all_num=0;
  int select_num=0;
  scanf("%d %d",&all_num, &select_num);
  int point[1000];
  for(int i=0;i<all_num;i++){
    scanf("%d",&point[i]);
  }
  int point_sum = 0;
  for (int j=0;j<all_num;j++){
    point_sum += point[j];
  }
  int select_ok = 0;
  int judgement = point_sum /(4*select_num);
  for (int k=0;k<all_num;k++){
    if(point[k] >= judgement){
      select_ok += 1;
    }
  }
  if(select_ok < select_num){
    printf("no");
  } else {
    printf("yes");
  }
  return 0; 
}