#include<iostream>
#include<math.h>
#include<algorithm>
using namespace std;
#define int long long

const int N = 2e5 + 5, p = 1e9 + 7;
pair<int, int> nums[N], heap[N];
int ans, sum, arr[N]; double Logarr[N];

int power(int a, int b)
{
	int tmp = 2, ans = 1;
	while (b > 0)
	{
		if (b % 2) ans = (ans * tmp) % p;
		tmp = (tmp * tmp) % p; b /= 2;
	}
	return (a * ans) % p;
}

signed main()
{
	int n, k; cin >> n >> k;
	for (int i = 1; i <= n; i++)
	{
		cin >> arr[i];
	}
	sort(arr + 1, arr + n + 1);
	for (int i = 1; i <= n; i++)
	{
		Logarr[i] = log2(arr[i]);
	}

	int stop = n, times = 0;
	int left = 1, right = n;
	while (left <= right)
	{
		int mid = (left + right) / 2; sum = 0;
		for (int i = 1; i < mid; i++)
		{
			sum += floor(Logarr[mid] - Logarr[i]);
		}

		if (sum <= k)
		{
			left = mid + 1;
		}
		else
		{
			stop = mid - 1;
			right = mid - 1;
		}

	}
	times = k - sum;

	for (int i = 1; i < stop; i++)
	{
		arr[i] = power(arr[i], floor(Logarr[stop] - Logarr[i]));
	}
	int t = times / stop, s = times - t * stop;
	for (int i = 1; i <= stop; i++)
	{
		if (i <= s) arr[i] = power(arr[i], t + 1);
		else arr[i] = power(arr[i], t);
	}

	for (int i = 1; i <= n; i++)
	{
		ans += arr[i]; ans %= p;
	}
	cout << ans;

	return 0;
}