/* ---------- STL Libraries ---------- */

// IO library
#include <cstdio>
#include <fstream>
#include <iomanip>
#include <ios>
#include <iostream>

// algorithm library
#include <algorithm>
#include <cmath>
#include <numeric>
#include <random>

// container library
#include <array>
#include <bitset>
#include <deque>
#include <map>
#include <queue>
#include <set>
#include <string>
#include <tuple>
#include <vector>

/* ---------- Namespace ---------- */

using namespace std;

/* ---------- Type Abbreviation ---------- */

using ll = long long;

template <typename T>
using PQ = priority_queue<T>;
template <typename T>
using GPQ = priority_queue<T, vector<T>, greater<T>>;

#define mp make_pair
#define mt make_tuple

/* ---------- conversion ---------- */

#define INT(c) static_cast<int>(c)
#define CHAR(n) static_cast<char>(n)
#define LL(n) static_cast<ll>(n)
#define DOUBLE(n) static_cast<double>(n)

/* ---------- container ---------- */

#define gsort(b, e) sort(b, e, greater<decltype(*b)>())

/* ----------- debug ---------- */

template <class T>
ostream& operator<<(ostream& os, vector<T> v) {
    os << "[";
    for (auto vv : v)
        os << vv << ",";
    return os << "]";
}

template <class T>
ostream& operator<<(ostream& os, set<T> v) {
    os << "[";
    for (auto vv : v)
        os << vv << ",";
    return os << "]";
}

template <class L, class R>
ostream& operator<<(ostream& os, pair<L, R> p) {
    return os << "(" << p.first << "," << p.second << ")";
}

/* ---------- Constants ---------- */

// const ll MOD = 1e9 + 7;
// const int INF = 1 << 25;
// const ll INF = 1LL << 50;
// const double PI = acos(-1);
// const double EPS = 1e-10;
// mt19937 mert(LL(time(0)));

/* ---------- Short Functions ---------- */

template <typename T>
inline T sq(T a) { return a * a; }

template <typename T>
T gcd(T a, T b) {
    if (a > b) return gcd(b, a);
    return a == 0 ? b : gcd(b % a, a);
}

template <typename T, typename U>
T mypow(T b, U n) {
    if (n == 0) return 1;
    if (n == 1) return b /* % MOD */;
    if (n % 2 == 0) {
        return mypow(b * b /* % MOD */, n / 2);
    } else {
        return mypow(b, n - 1) * b /* % MOD */;
    }
}

ll pcnt(ll b) {
    return __builtin_popcountll(b);
}

/* v-v-v-v-v-v-v-v-v Main Part v-v-v-v-v-v-v-v-v */

int main() {
    int N, K;
    cin >> N >> K;

    ll sum[N + 1];
    sum[0] = 0;
    for (int i = 1; i <= N; ++i) {
        ll a;
        cin >> a;
        sum[i] = sum[i - 1] + a;
    }

    vector<ll> S;
    for (int i = 0; i < N; ++i) {
        for (int j = i + 1; j <= N; ++j) {
            S.push_back(sum[j] - sum[i]);
        }
    }

    ll ans = 0;

    while (!S.empty()) {
        // cout << ans << ":" << S << endl;

        vector<ll> nums[50];
        for (ll n : S) {
            for (int k = 49; k >= 0; --k) {
                if (n & (1LL << k)) {
                    nums[k].push_back(n);
                }
            }
        }

        S.clear();

        for (int k = 49; k >= 0; --k) {
            if (nums[k].size() >= K) {
                ans |= (1LL << k);
                for (ll n : nums[k]) {
                    S.push_back(n ^ (1LL << k));
                }
                break;
            }
        }
    }

    cout << ans << endl;
    return 0;
}


Measured memory_bytes: 90220