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/*
Notice:
- This account submits solutions that result from the collaboration of two (non-Polish) individuals.
- We acknowledge that our participation is completely unofficial.
- We just want to be able to submit our solutions until the end of the week. Thank you :)!
*/
#include <cstdio>
#include <cstring>
#include <iostream>

using namespace std;
typedef long long int64;

const int kMaxN = 210;
const int kMaxB = 63;
const int64 kInf = (1LL<<61);
int64 dp[kMaxB + 1][kMaxN][kMaxN][2];
int64 a[kMaxN], pre[kMaxN];

void Reset() {
}

bool Solve() {
    Reset();
    int n;
    long long m;

    if (!(cin >> n >> m)) {
        return false;
    }

    for (int i = 1; i <= n; ++i) {
        cin >> a[i];
    }

    for (int i = 1; i <= n; ++i) {
        pre[i] = pre[i - 1] + a[i];
    }

    // Valid base cases are segments of 1 element, using 0 bits.
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= n; ++j) {
            dp[0][i][j][false] = dp[0][i][j][true] = -kInf;
        }

        dp[0][i][i][false] = dp[0][i][i][true] = 0;
    }

    for (int bit = 1; bit <= kMaxB; ++bit) {
        for (int i = 1; i <= n; ++i) {
            for (int j = i; j <= n; ++j) {
                // Put all zeros or all ones.
                dp[bit][i][j][false] = max(
                    dp[bit - 1][i][j][false],
                    dp[bit - 1][i][j][false] + pre[j] - pre[i - 1]);

                if ((m >> (bit - 1))&1) {
                    dp[bit][i][j][true] = max(dp[bit - 1][i][j][false], 
                        dp[bit - 1][i][j][true] + pre[j] - pre[i - 1]);
                } else {
                    dp[bit][i][j][true] = dp[bit - 1][i][j][true];
                }

                // Split into 2 sections.
                for (int k = i; k < j; ++k) {
                    // Split into [i, k], [k + 1, j].
                    dp[bit][i][j][false] = max(dp[bit][i][j][false], 
                        dp[bit - 1][i][k][false] + dp[bit - 1][k + 1][j][false] + pre[j] - pre[k]);

                    if ((m >> (bit - 1))&1) {
                        dp[bit][i][j][true] = max(dp[bit][i][j][true],
                            dp[bit - 1][i][k][false] + dp[bit - 1][k + 1][j][true] + pre[j] - pre[k]);
                    }
                }
            }
        }
    }

    cout << dp[kMaxB][1][n][true] << "\n";


    return true;
}

int main() {
    while(Solve());
}