#include <bits/stdc++.h>
using namespace std;
#define int long long
const int N = 100010;
int n, m;
int a[N];
bool check(int mid)
{
	vector<int> v;
	for (int i = 2; i <= n; i ++ )
		if (i != mid) v.push_back(a[i]);
	sort(v.begin(), v.end(), greater<int>());
	vector<int> v2;
	for (int i = (int)v.size() - 1; i >= 0; i -= 2)
		v2.push_back(v[i] + v[i - 1]);
	int sum = 0;
	for (int i : v2) sum += (i > a[mid] + a[1]);
	return sum < m; 
}
signed main()
{
	ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
	cin >> n >> m;
	a[n + 1] = -1;
	for (int i = 1; i <= n; i ++ )
		cin >> a[i];
	sort(a + 2, a + n + 1);
	int l = 2, r = n, res = n + 1;
	while (l <= r)
	{
		int mid = l + r >> 1;
		if (check(mid)) r = mid - 1, res = mid;
		else l = mid + 1;
	}
	cout << a[res];
	return 0;
}