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#include <bits/stdc++.h>
#include <math.h>
#include <chrono>
using namespace std;
//#pragma GCC optimize("-O3")
#define endl "\n"
#define mp make_pair
#define st first
#define nd second
#define pii pair<int, int>
#define pb push_back
#define _upgrade ios_base::sync_with_stdio(0), cout.setf(ios::fixed), cout.precision(10) //cin.tie(0); cout.tie(0);
#define REP(i, n) for (int i = 0; i < (n); ++i)
#define FWD(i, a, b) for (int i = (a); i < (b); ++i)
#define rep(i, n) for (int i = 0; i < (n); ++i)
#define fwd(i, a, b) for (int i = (a); i < (b); ++i)
#define all(c) (c).begin(), (c).end()
#define what(x) cerr << #x << " is " << x << endl;
#define int long long
#define highest(x) (63 - __builtin_clzll(x))

const int MAXN = 203;
const int inf = 1e17;
const int emp = 7e18 + rand();

int S[MAXN][MAXN];
int M[MAXN][MAXN][MAXN];
map<int, int> visited;
int n, k;
vector<int> D;

int pierwszy(int val)
{
    return (1ll << (highest(val))) - 1;
}
int drugi(int val)
{
    return val - (1ll << (highest(val)));
}

int get(int val)
{
    //cerr << val << " " << (lower_bound(all(D), val) - D.begin()) << endl;
    // return 0;
    return lower_bound(all(D), val) - D.begin();
}

int solve(int p, int q, int val)
{
    if (p > q)
        return 0;
    if (val < 0)
    {
        cerr << "wtf? " << val << endl;
        exit(-1);
    }

    if (val == 0)
        M[p][q][get(val)] = ((p == q) ? 0 : -inf);

    if (M[p][q][get(val)] != emp)
        return M[p][q][get(val)];

    int odp = -inf;

    for (int i = p; i <= q + 1; i++)
    {
        odp = max(odp, solve(p, i - 1, pierwszy(val)) + solve(i, q, drugi(val)) + S[i][q]);
        // cerr << val << " " << pierwszy(val) << " " << drugi(val) << endl;
        // cerr << p << " " << i << " " << q << " " << val << " " << solve(p, i - 1, pierwszy(val)) << " " << solve(i, q, drugi(val)) << " " << S[i][q] << " " << solve(p, i - 1, pierwszy(val)) + solve(i, q, drugi(val)) + S[i][q] << endl;
    }

    return M[p][q][get(val)] = odp;
}

void solve()
{
    for (int p = 0; p < n; p++)
        for (int q = 0; q < n; q++)
            M[p][q][0] = ((p == q) ? 0 : -inf);

    for (int l = 1; l < D.size(); l++)
    {
        int val = D[l];
        int pier = get(pierwszy(val));
        int dru = get(drugi(val));
        for (int p = 0; p < n; p++)
            for (int q = p; q < n; q++)
            {
                int odp = -inf;
                for (int i = p; i < q; i++)
                    odp = max(odp, M[p][i][pier] + M[i + 1][q][dru] + S[i + 1][q]);
                odp = max(odp, M[p][q][dru] + S[p][q]);
                odp = max(odp, M[p][q][pier]);
                M[p][q][l] = odp;
            }
    }
}

void dfs(int x)
{

    visited[x] = 1;
    D.push_back(x);
    if (x == 0)
        return;
    if (visited[pierwszy(x)] == 0)
        dfs(pierwszy(x));
    if (visited[drugi(x)] == 0)
        dfs(drugi(x));
}

void pre()
{
    cin >> n >> k;
    vector<int> P(n);
    rep(i, n) cin >> P[i];
    rep(i, n) rep(j, n) for (int k = i; k <= j; k++)
        S[i][j] += P[k];

    dfs(k);
    sort(all(D));
    //cerr << D.size() << endl;
}

void debug()
{

    for (int d : D)
        cerr << d << " ";
    cerr << endl;
    /*
    set<int> S;
    for (int i = 0; i < n - 1; i++)
        for (int j = i; j < n; j++)
            for (auto P : M[i][j])
                S.insert(P.st);
    cerr << S.size() << endl;
    return;
    
    for (int i = 0; i < n - 1; i++)
        for (int j = i; j < n; j++)
        {
            cerr << "dla " << i << " " << j << " mapa wyglada tak: " << endl;
            for (auto P : M[i][j])
                cerr << P.st << " " << P.nd << endl;
        }
        */
}

main()
{
    _upgrade;
    pre();
    // debug();
    //exit(-1);
    solve();
    //solve(0, n - 1, k);

    cout << M[0][n - 1][get(k)] << endl;
    //debug();
    //cerr << highest(7) << " " << highest(1ll << 40) << " " << highest(0) << " " << highest(1) << endl;
}