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++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

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

#define ll long long
#define ull unsigned long long
#define vii vector<int>
#define pii pair<int,int>
#define pll pair<long long,long long>
#define pdd pair<double,double>
#define pldld pair<long long double, long long double>
#define ff first
#define ss second
#define pb push_back
#define read freopen("alu.txt","r",stdin);
#define write freopen("vorta.txt","w",stdout);
#define fastio ios::sync_with_stdio(false); cin.tie(NULL);
#define PI 2*acos(0.0)
#define DEBUG(x) cerr << #x << " = " << x << endl

const int MAX = 2e6 + 5, MOD = 1e9 + 7  , MAXLG = log2(MAX)+1;
const ll inf = 1e18 + 5;

int arr[MAX];
int main(){

    fastio;
    int n,m;
    cin>>n>>m;
    int sum = 0;
    for(int i=0; i<n; i++) cin>>arr[i], sum += arr[i];
    sort(arr,arr+n, greater<int>());
    bool ok = true;
    sum /= 4;
    sum /= m;
    for(int i=0; i<m; i++){
        if(arr[i] < sum) {ok = false; break;}
    }
    if(ok) cout<<"Yes\n";
    else cout<<"No\n";
}