#include<bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
const ll N = 1e6 + 5;
const ll mod = 1e9 + 7;
const ll inf = LLONG_MAX/5;
#define bit(x,y) ((x >> y) & 1)
vector<ll> b[N];
ll a[N];
ll get(ll l, ll r)
{
    ll ans = 0;
    ll i,j;
    for(i = l;i <= r;i++)
    {
        ans = max(ans,a[i]);
    }
    return ans;
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    ll n;
    ll i,j;
    cin >> n;
    for(i = 1;i <= n;i++) cin >> a[i];
    stack<ll> st;
    for(i = 1;i <= n;i++)
    {
        while(!st.empty() && a[st.top()] <= a[i])
        {
            b[i].push_back(st.top());
            st.pop();
        }
        if(!st.empty()) b[i].push_back(st.top());
        st.push(i);
    }
    ll q;
    cin >> q;
    while(q--)
    {
        ll l,r;
        cin >> l >> r;
        ll i,j;
        ll ans = 0;
        for(i = l;i <= r;i++)
        {
            for(auto s : b[i])
            {
                ll e = 2 * i - s;
                if(l <= s && e <= r)
                {
                    ans = max(ans,a[s] + a[i] + get(e,r));
                }
            }
        }
        cout << ans << "\n";
    }
}
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