#include <bits/stdc++.h>

using namespace std;
using i64 = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n, k;
    cin >> n >> k;

    priority_queue<int, vector<int>, greater<int>> q;
    for (int i = 0; i < n; i ++ ) {
        int x;
        cin >> x;
        q.push(x);
    }

    for (int i = 0; i < k; i ++ ) {
        auto x = q.top();
        q.pop();

        q.push(x * 2);
    }

    i64 ans = 0;
    while (q.size()) {
        auto x = q.top();
        q.pop();

        ans += x;
    }
    cout << ans << "\n";

    return 0;
}