#include <bits/stdc++.h>
using namespace std;
int n;
vector<int> vals;
int main() {
cin >> n;
vals.resize(n);
for (int i = 0; i < n; i++)
cin >> vals[i];
int back_rollsum = 0;
int forw_rollsum = 0;
for (int i = 0; i < (n + 1) / 2; i++) {
back_rollsum += vals[(n - i) % n];
forw_rollsum += vals[i];
}
int ans = 0;
for (int i = 0; i < n; i++) {
int localans = min(back_rollsum, forw_rollsum);
if (localans > ans) {
ans = localans;
}
back_rollsum += vals[(i + 1) % n] - vals[(n + 1 + i - n / 2) % n];
forw_rollsum += vals[(i + n / 2) % n] - vals[i % n];
}
cerr << ans << endl;
return 0;
}
