#include <bits/stdc++.h>
using namespace std;
typedef long long int ll;
typedef pair <int,int> ii;
const int N = 2e5 + 5;
const int inf = 2e9;
const int SQ = 300;
int n,q,a[N],suff[N];
ll ans;
void f(int l,int r,int optl,int optr) {
if (l > r)
return;
int mid = (l + r) / 2;
int newopt = mid - 1;
ll val = 0;
for (int i = min(mid - 1,optr) ; i >= optl ; i--) {
if (2 * mid - i > n)
break;
if ((ll)a[mid] + a[i] + suff[2 * mid - i] >= val) {
val = (ll)a[mid] + a[i] + suff[2 * mid - i];
newopt = i;
ans = max(ans,val);
}
}
// cerr << mid << " " << newopt << endl;
f(l,mid - 1,newopt,optr);
f(mid + 1,r,optl,newopt);
}
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL) ; cout.tie(NULL);
cin >> n;
for (int i = 1 ; i <= n ; i++)
cin >> a[i];
cin >> q;
assert(q == 1);
while(q--) {
int l,r;
cin >> l >> r;
assert(l == 1);
assert(r == n);
}
for (int i = n ; i >= 1 ; i--)
suff[i] = max(suff[i + 1],a[i]);
f(2,n,1,n);
cout << ans << endl;
}
