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#include <bits/stdc++.h>

using namespace std;

typedef unsigned uint;
typedef long long ll;
typedef unsigned long long ull;
typedef long double ldbl;
typedef pair<int, int> pii;
typedef pair<uint, uint> puu;
typedef pair<ll, ll> pll;
typedef pair<ull, ull> pull;
typedef pair<double, double> pdd;
typedef vector<int> vi;
typedef vector<uint> vu;
typedef vector<ll> vll;
typedef vector<ull> vull;
typedef vector<pii> vpii;
typedef vector<puu> vpuu;
typedef vector<pll> vpll;
typedef vector<pull> vpull;
typedef vector<string> vstr;
typedef vector<double> vdbl;
typedef vector<ldbl> vldbl;
#define pb push_back
#define ppb pop_back
#define pfr push_front
#define ppfr pop_front
#define emp emplace
#define empb emplace_back
#define be begin
#define rbe rbegin
#define all(x) (x).be(), (x).end()
#define rall(x) (x).rbe(), (x).rend()
#define fir first
#define sec second
#define mkp make_pair
#define brif(cond) if (cond) break
#define ctif(cond) if (cond) continue
#define retif(cond) if (cond) return
void canhazfast() {ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);}
template<typename T> T gcd(T a, T b) {return b ? gcd(b, a%b) : a;}
template<typename T> T extgcd(T a, T b, T &x, T &y)
{
    T x0 = 1, y0 = 0, x1 = 0, y1 = 1;
    while (b) {
        T q = a/b; a %= b; swap(a, b);
        x0 -= q*x1; swap(x0, x1);
        y0 -= q*y1; swap(y0, y1);
    }
    x = x0; y = y0; return a;
}
int ctz(uint x) {return __builtin_ctz(x);}
int ctzll(ull x) {return __builtin_ctzll(x);}
int clz(uint x) {return __builtin_clz(x);}
int clzll(ull x) {return __builtin_clzll(x);}
int popcnt(uint x) {return __builtin_popcount(x);}
int popcntll(ull x) {return __builtin_popcountll(x);}
int bsr(uint x) {return 31^clz(x);}
int bsrll(ull x) {return 63^clzll(x);}

#define N 256
#define C 64
#define INF ((ll)4e18)
#define MX ((ll)12e17)

ll a[N];
ll sa[N];
//bitset<N> good[2][2][N];
ll dp[2][2][N][N]; /// ([i]) [f][b][e]

template<typename T>
void umin(T &a, T b) { a = min(a, b); }

template<typename T>
void umax(T &a, T b) { a = max(a, b); }

int main()
{
    canhazfast();

    int n, k;
    ull m;
    ll ans = -INF;
    ll (*pre)[N][N] = dp[0];
    ll (*nxt)[N][N] = dp[1];
    //bitset<N> (*gpre)[N] = good[0];
    //bitset<N> (*gnxt)[N] = good[1];

    cin >> n >> m;
    for (int i = 0; i < n; ++i) cin >> a[i];
    retif(m == 0) cout << "0\n", 0;
    k = bsrll(m);
    for (int i = 0; i < n; ++i) sa[i+1] = sa[i]+a[i];

    /// init dp lvl 0
    for (int b = 0; b <= n; ++b) {
        //gpre[1][b][b] = true;
        for (int e = b+1; e <= n; ++e) {
            int sz = e-b;
            //gpre[1][b][e] = sz < 3;
            switch (sz) {
            case 1:
                pre[1][b][e] = max(a[b], 0LL);
                break;
            case 2:
                pre[1][b][e] = a[b+1];
                break;
            default:
                pre[1][b][e] = -INF;
                break;
            }
        }
    }
    if (m&1) {
        for (int b = 0; b <= n; ++b) {
            //gpre[0][b] = gpre[1][b];
            copy(pre[1][b], pre[1][b]+n+1, pre[0][b]);
        }
    } else {
        for (int b = 0; b <= n; ++b) {
            for (int e = b; e <= n; ++e) {
                int sz = e-b;
                //gpre[0][b][e] = sz < 2;
                pre[0][b][e] = sz < 2 ? 0 : -INF;
            }
        }
    }

    /// run dp
    for (int i = 0; i < k; ++i) {
        /// f = 1
        for (int b = 0; b <= n; ++b) {
            //gnxt[1][b][b] = true;
            nxt[1][b][b] = 0;
            for (int e = b+1; e <= n; ++e) {
                //bool tmp = false;
                nxt[1][b][e] = -INF;
                for (int j = b; j <= e; ++j) {
                    //ctif(!gpre[1][b][j] || !gpre[1][j][e]);
                    //tmp = true;
                    umax(nxt[1][b][e], pre[1][b][j]+pre[1][j][e]+sa[e]-sa[j]);
                }
                //gnxt[1][b][e] = tmp;
                if (nxt[1][b][e] <= -MX) nxt[1][b][e] = -INF;
            }
        }

        /// f = 0
        if ((m>>(i+1)&1)) {
            for (int b = 0; b <= n; ++b) {
                //gnxt[0][b][b] = true;
                nxt[0][b][b] = 0;
                for (int e = b+1; e <= n; ++e) {
                    //bool tmp = false;
                    nxt[0][b][e] = -INF;
                    for (int j = b; j <= e; ++j) {
                        //ctif(!gpre[1][b][j] || !gpre[0][j][e]);
                        //tmp = true;
                        umax(nxt[0][b][e], pre[1][b][j]+pre[0][j][e]+sa[e]-sa[j]);
                    }
                    //gnxt[0][b][e] = tmp;
                    if (nxt[0][b][e] <= -MX) nxt[0][b][e] = -INF;
                }
            }
        } else {
            for (int b = 0; b <= n; ++b) {
                //gnxt[0][b] = gpre[0][b];
                copy(pre[0][b], pre[0][b]+n+1, nxt[0][b]);
            }
        }

        swap(pre, nxt);
        //swap(gpre, gnxt);
    }

    ans = pre[0][0][n];
    cout << ans << '\n';

    return 0;
}