#include <bits/stdc++.h>
#define ll long long

using namespace std;
const ll N=801010;
const ll p=1000000007;

ll n,K;
ll a[N],b[N];
priority_queue <ll, vector <ll>, greater<ll> > q;

int main() {
	scanf("%lld%lld",&n,&K);
	ll ans = 0, sum = 1000;
	for(ll i=1;i<=n;i++) {
		scanf("%lld",&a[i]);
		q.push(a[i]);
	}
	if(sum>=K) {
		while(K--) {
			ll u = q.top(); q.pop();
			u = u*2 %p;
			q.push(u);
		}
		while(!q.empty()) {
			(ans += q.top()) %= p; q.pop();
		}
		cout<<ans;
		return 0;
	}
	ll qian = sum;
	ll ci = (K-sum) / n;
	ll mi = 1;
	while(ci--) mi = mi * 2 %p;
	qian += (K-sum) % n;
	while(qian--) {
		ll u = q.top(); q.pop();
		u = u*2 %p;
		q.push(u);
	}
	while(!q.empty()) {
		ll u = q.top(); q.pop();
		(ans += u * mi %p) %= p;
	}
	cout<<(ans%p+p)%p;
	return 0;
}

/*

3 10
1

*/