#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main() {
    int n, k;
    cin >> n >> k;

    vector<ll> x;
    x.push_back(0);
    for (int i = 0; i < n; i++) {
        int a;
        cin >> a;

        int l = x.size();
        x.resize(l * 2);
        for (int i = 0; i < l; i++) {
            x[l + i] = x[i] + a;
        }
        l *= 2;
        if (l > k) {
            sort(x.begin(), x.end(), greater<>());
            x.resize(k);
        }
    }
    sort(x.begin(), x.end(), greater<>());
    cout << x.back() << endl;

    return 0;
}