#include<bits/stdc++.h>
using namespace std;
int main(){
ios::sync_with_stdio(false);
cin.tie(nullptr);
int N;
cin >> N;
vector<int> A(N);
for(int &x : A) cin >> x; // A[i] <= 2000
for(int i = 0;i < N;i++) A.push_back(A[i]);
for(int i = 0;i < N;i++) A.push_back(A[i]);
vector<int> ps(3 * N);
for(int i = 0;i < 3 * N;i++){
ps[i] = A[i];
if(i) ps[i] += ps[i-1];
}
auto Sum = [&](int l, int r)->int{
int res = ps[r];
if(l) res -= ps[l - 1];
return res;
};
int ans = 0;
int K = (N + 1) / 2;
for(int i = N;i < (N > 10000 ? N+1 :2 * N);i++){
int res = 2000 * N;
for(int start = i - K + 1;start <= i;++start){
res = min(res, Sum(start, start + K - 1));
}
ans = max(ans, res);
}
cout << ans << '\n';
return 0;
}
