#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pb push_back
#define dd(x) cout<<#x<<" is "<<x<<endl;
#define dd2(x,y) cout<<#x<<" is "<<x<<" "<<#y<<" is "<<y<<endl;
#define dl(x) cout<<#x<<" is "<<endl; for(int i=1; i<9; i++) cout<<x[i]<<' '; cout<<endl;
#define fi first
#define se second
typedef pair<int,int> pii;
const int N = 5e5+5;
int a[N];
int b[N*2];
int p[N*2];
deque<int>v;
signed main(){
ios::sync_with_stdio(0); cin.tie(0);
int n; cin>>n;
for(int i=1; i<=n; i++) cin>>a[i];
v.pb(0); //placeholder for 1 index
for(int i=1; i<=n; i++) v.pb(a[i]);
for(int i=1; i<=n; i++) v.pb(a[i]);
int ans = 0;
for(int x=1; x<=n; x++){
//dl(v)
for(int i=1; i<=2*n; i++) p[i] = p[i-1]+v[i];
int val = LLONG_MAX;
for(int i=n+1; i<=n+(n+1)/2; i++){
int j = i-(n+1)/2;
//dd2(p[i],p[j])
val = min(val,p[i]-p[j]);
}
ans = max(ans,val);
v.pop_front();
v.pb(v.front());
v.pop_front();
v.push_front(0);
}
cout<<ans;
return 0;
}
