#include <bits/stdc++.h>

using namespace std;
using i64 = long long;
const int INF =  1e9 + 7;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n, k;
    cin >> n >> k;
    priority_queue <i64, vector<i64>, greater<i64>> q;
    i64 sum = 0;

    for (int i = 1; i <= n; i++) {
        i64 a; 
        cin >> a;
        sum = (sum + a) % INF;
        q.push(a);
    }

    for (int i = 1; i <= k; i++) {
        int p = q.top();
        q.pop();
        sum = (sum + p) % INF;
        p = (p * 2);
        q.push(p);
    }
    cout << sum;

    return 0;
}