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 9.2.1) (judge verdict: Wrong Answer)

#include<bits/stdc++.h>
using namespace std;

int m,n;
int  a[102];

void solve(){
    cin >> n >> m;
    int s=0;
    for(int i=0;i<n;++i) {
        cin >> a[i];
        s+=a[i];
    }
    s/=(4*m);
    int cnt=0;
    for(int i=0;i<n;++i)
        cnt += (a[i]>=s);
    cout << (cnt >= m  ?  "Yes" : "No") << "\n";
}

int main(){
    ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
    int t=1;
    while(t--)
        solve();
    return  0;
}