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 Go (1.14.1) (judge verdict: Wrong Answer)

package main

import (
	"fmt"
	"sort"
)

func sliceUnique(target []int) (unique []int) {
	m := map[int]bool{}

	for _, v := range target {
		if !m[v] {
			m[v] = true
			unique = append(unique, v)
		}
	}

	return unique
}

func main() {
	var n, m int
	fmt.Scan(&n, &m)
	if m > n {
		return
	}
	points := make([]int, n)
	sum := 0

	for i:=0; i<n; i++{
		fmt.Scan(&points[i])
		sum += points[i]
	}


	sort.Sort(sort.Reverse(sort.IntSlice(points)))
	unique_points := sliceUnique(points)

	if float64(unique_points[m-1]) >= float64(sum / (4 * m)) {
		fmt.Println("Yes")
	}else{
		fmt.Print("No")
	}

}