#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(x) (x).begin(), (x).end()
#define MP make_pair
const int N = 100500;
int n;
int a[N], p[N];
int get_sum(int l, int r){
if (l <= r){
return p[r] - (l == 0 ? 0 : p[l - 1]);
} else {
return p[r] + (p[n - 1] - p[l - 1]);
}
}
int t[4 * N];
int val[N];
void build(int v, int tl, int tr){
if (tl == tr){
t[v] = val[tl];
return;
}
int tm = (tl + tr) >> 1;
build(v << 1, tl, tm);
build(v << 1 | 1, tm + 1, tr);
t[v] = max(t[v << 1], t[v << 1 | 1]);
}
int get(int v, int tl, int tr, int l, int r){
if (l <= tl && tr <= r) return t[v];
if (tl > r || tr < l) return 0;
int tm = (tl + tr) >> 1;
return max(get(v << 1, tl, tm, l, r), get(v << 1 | 1, tm + 1, tr, l, r));
}
int get(int l, int r){
if (l <= r){
return get(1, 0, n - 1, l, r);
} else {
return max(get(1, 0, n - 1, l, n - 1), get(1, 0, n - 1, 0, r));
}
}
void solve(){
cin >> n;
for (int i = 0; i < n; i++){
cin >> a[i];
p[i] = a[i] + (i > 0 ? p[i - 1] : 0);
}
for (int i = 0; i < n; i++){
int l = (i - n / 2 + 1 + n) % n;
val[i] = get_sum(l, i);
}
build(1, 0, n - 1);
int ans = 0;
for (int i = 0; i < n; i++){
int l = (i + n / 2) % n, r = (i + n - 1) % n;
int mx = get(l, r);
ans = max(ans, get_sum(0, n - 1) - mx);
}
cout << ans << endl;
}
int main() {
ios_base::sync_with_stdio(false);
#ifdef LOCAL
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
solve();
return 0;
}
