#include <bits/stdc++.h>
using namespace std;
int main() {
// freopen("main.in", "r", stdin);
// freopen(".out", "w", stdout);
int n; cin >> n;
vector<int> a(2 * n + 1);
a[0] = 0;
multiset<int> m;
int wsz = (n + 1) / 2;
for (int i = 1; i <= n; i++) cin >> a[i];
for (int i = 0; i < n; i++) a[n + i + 1] = a[i + 1];
for (int i = 1; i <= 2 * n; i++) a[i] += a[i - 1];
vector<int> mins(n+1, INT_MAX);
for (int i = 1; i < 2*n + 1; i++) {
if (i + wsz - 1 <= 2*n) {
int sum = a[i+wsz-1] - a[i-1];
m.insert(sum);
}
if (i > wsz) {
int old = a[i-1] - a[i-1-wsz];
m.erase(m.find(old));
}
int pos = ((i-1)%n) + 1;
if (!m.empty()) mins[pos] = min(mins[pos], *m.begin());
}
int ans = 0;
for (int i = 1; i <= n; ++i) ans = max(ans, mins[i]);
cout << ans << endl;
}
