#include <bits/stdc++.h>
#define debug(x) cout << #x << ' ' << x << '\n'
#define endl '\n'

using namespace std;

typedef pair<int, int> PII;
typedef long long ll;
const int N = 200010, mod = 1e9 + 7, inf = 0x3f3f3f3f;

int n, k;
ll a[N];

ll ksm(ll a, ll b) {
	a %= mod;
	b %= mod;
	ll res = 1;
	while(b) {
		if (b & 1) res = (res * a) % mod;
		b >>= 1;
		a = a * a % mod;
	}
	return res % mod;
}

void solve()
{
	cin >> n >> k;

	auto cmp = [](ll &a, ll &b) {
		return a > b;
	};

	priority_queue<ll, vector<ll>, decltype(cmp)> q(cmp);

	for (int i = 1; i <= n; i ++) {
		cin >> a[i];
		q.push(a[i]);
	}
	
	ll t = q.top();
	while(k && t < mod) {
		q.pop();
		q.push(t * 2);
		t = q.top();
		k --;
	}

	n = 0;
	while(q.size()) {
		a[++n] = q.top();
		q.pop();
	}
	
	ll p = k / n;
	ll ans = 0;
	int sum = k % n;
	for (int i = 1; i <= n; i ++) {
		if (sum) {
			ans += 2 * a[i] * ksm(2, p) % mod;
			sum --;
		} else {
			ans += a[i] * ksm(2, p) % mod;
		}
	}
	
	cout << ans << endl;

}

int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0), cout.tie(0);

	solve();

	return 0;
}