This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include <bits/stdc++.h>
/*
#pragma GCC optimize("O3")
#pragma GCC target ("avx2")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("unroll-loops")
*/
using namespace std;
#define F first
#define S second
#define pb push_back    
#define nl '\n'
#define all(z) (z).begin(), (z).end()
#define sz(x) (int) (x).size()
#define IOS ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
typedef long long ll;
long long n, m, a, b, y, x, k, ti, h;
string s, ss;
char c, ch;
long double db;                                                            
                                                                           
const int N = 1e5 + 7;                                                     
const int INF = INT_MAX;                                                   
int mod = 1e9 + 7;
vector<ll> v, pref;
ll ans = LLONG_MAX;
ll cur = 0;
ll cnt = 0;    
void solve(int st, int prev) {
	cnt++;
	if (cnt == k) {
		ll noww = cur;
		cur |= (pref[n] - pref[prev]);
		ans = min(ans, cur);
		cur = noww;
		cnt--;
		return;
	}
	ll now = cur;
	for (int i = st; i < n; ++i) {
		cur |= (pref[i] - pref[prev]);
		solve(i + 1, i);
		cur = now;
	}
	cnt--;
}
void Main() {
	cin >> n >> a >> b;
	v.resize(n + 1);
	pref.assign(n + 1, 0);
	for (int i = 1; i <= n; ++i) {
		cin >> v[i];
		pref[i] = pref[i - 1] + v[i];
	}
	for (int i = a; i <= b; ++i) {
		k = i;
		solve(1, 0);
	}
	cout << ans;
	return;
}
int main () {                                                                           
    IOS;
#ifdef BATYA
    freopen(".in", "r", stdin);
#endif
	ti = 1;
	//cin >> ti;
	while (ti--)
		Main();
	return 0;	
}
//doner           	 
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