#include <bits/stdc++.h>
using namespace std;
#define int long long
const int MAXN = 5e5 + 2;
int n;
int a[MAXN], sums[MAXN];
signed main() {
cin >> n;
int sum = 0;
int half = (n + 1) / 2;
for (int i = 0; i < n; i++) {
cin >> a[i];
if (i < half) {
sum += a[i];
}
}
for (int i = 0; i <= n; i++) {
sums[i % n] = sum;
sum += a[(i + half) % n];
sum -= a[i % n];
}
int ans = 0;
for (int i = 0; i < n; i++) {
int L = (i - half + 1 + n) % n;
int R = i;
int min_val = LLONG_MAX;
if (R >= L) {
for (int j = L; j <= R; j++) {
min_val = min(min_val, sums[j]);
}
} else {
for (int j = L; j < n; j++) {
min_val = min(min_val, sums[j]);
}
for (int j = 0; j <= R; j++) {
min_val = min(min_val, sums[j]);
}
}
ans = max(ans, min_val);
}
cout << ans;
}
