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>
#include <iostream>
#include <cmath>
#include <iomanip>
#include <vector>
#include <map>
#include <stack>
#include <queue>
 
using namespace std;
 
#define ll long long
#define pb push_back
#define el '\n'
#define mpair make_pair
#define MASK(i) (1LL << (i))
#define BIT(mask, i) (((mask) >> (i)) & 1)
#define fi first
#define se second
 
/* Author: Pham Gia Phuoc */
 
const ll MOD = (ll)(1e9) + 1LL * 19972207;
 
template <class T1, class T2>
    void add(T1 &a, T2 b){
        a += b;
        if(a >= MOD) a -= MOD;
    }
 
template <class T1, class T2>
    void sub(T1 &a, T2 b){
        a -= b;
        if(a < 0) a += MOD;
    }
 
template <class T1, class T2>
    bool minimize(T1 &a, T2 b){
        if(a > b){a = b; return true;} return false;
    }
 
template <class T1, class T2>
    bool maximize(T1 &a, T2 b){
        if(a < b){a = b; return true;} return false;
    }
 
/** END OF TEMPLATE. DRINK A CUP OF COFFEE BEFORE READING MY CODE **/
 
const int MAX = 2010;
const ll INF = (ll) 1e18 + 67LL;
const int oo = (int)(1e9 + 7);
const int NUM_BIT = 62;
#define FOR(i, a, b) for(int i = a; i <= b; i++)
int N, A, B;
long long ages[MAX];
 
void init(){
    cin >> N >> A >> B;
    FOR(i, 1, N) cin >> ages[i];
}
namespace subtask1{
    bool check(){
        return N <= 20;
    }
    long long solve(){
        long long ans = INF;
        for(int mask = 0; mask < MASK(N); mask++){
            if(__builtin_popcount(mask) == 0) continue;
            int cntGroup = __builtin_popcount(mask) + (BIT(mask, N - 1) == 1 ? 0 : 1);
            if(cntGroup < A || cntGroup > B) continue;
            
            long long sum = 0, sumor = -1;
            for(int i = 0; i < N; i++){
                sum += ages[i + 1];
                if(BIT(mask, i)){
                    sumor = (sumor == -1) ? sum : (sumor | sum);
                    sum = 0;
                }
            }
            if(!BIT(mask, N - 1)){
                // sum += ages[N];
                sumor = (sumor == -1) ? sum : (sumor | sum);
            }
            minimize(ans, sumor);
        }
        return ans;
    }
}
void solve(){
    if(subtask1::check()){cout << subtask1::solve(); return;}
}
int main(){
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    #define test "test"
    srand(time(0));
    int t = 1;
    while(t--){
        // gen();
        init();
        solve();
    }
    
    return 0;
}
 
 
 
/*** ROAD TO VOI 2025 ***/
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