void main() {
	auto ip = readAs!(int[]), N = ip[0], K = ip[1];
	auto a = readAs!(int[]);
	int[][] arr;
	foreach(k; 1..N+1) {
		foreach(i; 0..N-k+1) {
			arr ~= a[i..k+i];
		}
	}
	auto m = arr.map!(i => i.sum).array.sort!"a > b"();
	ulong p = 1;
	ulong b = m[0].bitsSet.reduce!max;
	ulong c = 1;
	while(p < N) {
		//writefln("%s %s", b, m[p].bitsSet.reduce!max);
		if(m[p].bitsSet.reduce!max == b) {
			c++;
			p++;
			if(c == K) {
				writeln(m[p-K..p].reduce!((i, j) => i & j));
				return;
			}
		} else {
			b = m[p].bitsSet.reduce!max;
			c = 1;
		}
	}
	writeln(0);
}

// ===================================

import std.stdio;
import std.string;
import std.functional;
import std.algorithm;
import std.range;
import std.traits;
import std.math;
import std.container;
import std.bigint;
import std.numeric;
import std.conv;
import std.typecons;
import std.uni;
import std.ascii;
import std.bitmanip;
import core.bitop;

T readAs(T)() if (isBasicType!T) {
	return readln.chomp.to!T;
}
T readAs(T)() if (isArray!T) {
	return readln.split.to!T;
}

T[][] readMatrix(T)(uint height, uint width) if (!isSomeChar!T) {
	auto res = new T[][](height, width);
	foreach(i; 0..height) {
		res[i] = readAs!(T[]);
	}
	return res;
}

T[][] readMatrix(T)(uint height, uint width) if (isSomeChar!T) {
	auto res = new T[][](height, width);
	foreach(i; 0..height) {
		auto s = rs;
		foreach(j; 0..width) res[i][j] = s[j].to!T;
	}
	return res;
}

int ri() {
	return readAs!int;
}

double rd() {
	return readAs!double;
}

string rs() {
	return readln.chomp;
}
