#include<bits/stdc++.h>
#define int long long
#define ii pair<int, int>
using namespace std;
const int N = 5e5 + 5,
oo = 1e16;
int n, q;
int a[N];
vector<ii> query[N];
void maximize(int &x, int y) { x = max(x, y); }
struct SegmentTree {
ii T[N << 2];
int lz[N << 2];
void build(int s, int l, int r) {
if(l == r) {
T[s] = {a[l], -oo};
return;
}
int mid = l + r >> 1;
build(s << 1, l, mid); build(s << 1 | 1, mid + 1, r);
T[s] = max(T[s << 1], T[s << 1 | 1]);
}
void push(int s, int l, int r) {
if(lz[s] == 0) return;
int x = lz[s]; lz[s] = 0;
T[s << 1].second = max(T[s << 1].second, T[s << 1].first + x);
T[s << 1 | 1].second = max(T[s << 1 | 1].second, T[s << 1 | 1].first + x);
lz[s << 1] = max(lz[s << 1], x); lz[s << 1 | 1] = max(lz[s << 1 | 1], x);
}
void upd(int s, int l, int r, int u, int v, int x) {
if(r < u || l > v) return;
if(l >= u && r <= v) {
T[s].second = max(T[s].second, T[s].first + x);
lz[s] = max(lz[s], x);
return;
}
int mid = l + r >> 1;
push(s, l, r);
upd(s << 1, l, mid, u, v, x); upd(s << 1 | 1, mid + 1, r, u, v, x);
T[s].first = max(T[s << 1].first, T[s << 1 | 1].first);
T[s].second = max(T[s << 1].second, T[s << 1 | 1].second);
}
int get(int s, int l, int r, int u, int v) {
if(r < u || l > v) return -oo;
if(l >= u && r <= v) return T[s].second;
int mid = l + r >> 1;
push(s, l, r);
return max(get(s << 1, l, mid, u, v), get(s << 1 | 1, mid + 1, r, u, v));
}
} it;
int32_t main() {
cin.tie(0)->sync_with_stdio(0);
cin >> n;
for(int i = 1; i <= n; ++i) cin >> a[i];
it.build(1, 1, n);
cin >> q;
for(int i = 1; i <= q; ++i) {
int l, r; cin >> l >> r;
query[l].emplace_back(r, i);
}
auto update = [&](int i, int j) {
int value = a[i] + a[j];
it.upd(1, 1, n, 2 * j - i, n, value);
};
stack<int> st;
vector<int> ans(q + 1);
for(int i = n; i; --i) {
while(st.size() && a[st.top()] <= a[i]) update(i, st.top()), st.pop();
if(st.size()) update(i, st.top());
for(auto [r, idx] : query[i]) ans[idx] = it.get(1, 1, n, i, r);
st.push(i);
}
for(int i = 1; i <= q; ++i) cout << ans[i] << '\n';
}
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